abi.html: New.

2004-05-13  Benjamin Kosnik  <bkoz@redhat.com>

	* docs/html/abi.html: New.
	* docs/html/abi.txt: Remove.
	* docs/html/documentation.html: Add link.
	* testsuite/Makefile.am: Add files.
	* testsuite/Makefile.in: Regenerated.
	* testsuite/abi_check.cc: Move and modify code into...
	* testsuite/testsuite_abi.cc: Add.
	* testsuite/testsuite_abi.h: Add.

	* docs/html/17_intro/TODO: Update.
	* include/bits/stl_pair.h: Format.

From-SVN: r81781
This commit is contained in:
Benjamin Kosnik 2004-05-13 12:50:53 +00:00 committed by Benjamin Kosnik
parent f8f456c68a
commit 4b260c2013
11 changed files with 1565 additions and 861 deletions

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@ -1,3 +1,17 @@
2004-05-13 Benjamin Kosnik <bkoz@redhat.com>
* docs/html/abi.html: New.
* docs/html/abi.txt: Remove.
* docs/html/documentation.html: Add link.
* testsuite/Makefile.am: Add files.
* testsuite/Makefile.in: Regenerated.
* testsuite/abi_check.cc: Move and modify code into...
* testsuite/testsuite_abi.cc: Add.
* testsuite/testsuite_abi.h: Add.
* docs/html/17_intro/TODO: Update.
* include/bits/stl_pair.h: Format.
2004-05-06 Matthias Klose <doko@debian.org>
* include/backward/iterator.h: Add GPL copyright info,

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@ -2,16 +2,13 @@ std::allocator
- switch to mt_allocator with --enable-threads=posix.
- Try to figure out a way to switch allocators in a more elegant
manner, and make the default allocator configurable.
- persistent allocator
- global/extern allocator
std::string
- re-design for multi-paradigm, meta string class solution incorporating COW
- Policy-based design incorporating COW
vs. deep copy issues, MT scalability
See Andrei Alexandrescu, June 2001, C/C++ Users Journal
"Generic<Programming>: A Policy-Based basic_string Implementation"
@ -53,8 +50,6 @@ std::locale
- minimize ctype convertion in data facets, see numpunct/num_put/num_get
- finish caching data facets and using the caches
std::basic_filebuf, 27_io
- wfilebuf, get variable-encoding working and tested, including
@ -86,11 +81,11 @@ testsuite
- diffing generated output files
- provide testsuites for numerics.
- make check-abi needs to have full symbol checking. Scope the LSB
testsuite, see what's going on with the typeinfo etc. bits.
- provide testsuites for numerics.
- try to do a better job of ABI testing, with instantiations of all
standard-specified types checked, not just exported symbols.
@ -140,9 +135,6 @@ Nathan's commentary on cantrip, http://www.cantrip.org/cheaders.html
- auto_ptr: seems to be some disagreement on what is
standards-conformant behavior, specially on conversion operators.
- looks like deque::get_allocator not standards conformant or deque
allocator non-standard.
- list::assignment operator needs const_cast
- a cleaner division between pointers-to-value_type and true iterators

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@ -0,0 +1,857 @@
<?xml version="1.0" encoding="ISO-8859-1"?>
<!DOCTYPE html
PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<meta name="AUTHOR" content="bkoz@gcc.gnu.org (Benjamin Kosnik)" />
<meta name="KEYWORDS" content="C++, libstdc++, dynamic, shared, library, ABI, version" />
<meta name="DESCRIPTION" content="C++ Standard Library ABI" />
<meta name="GENERATOR" content="emacs and ten fingers" />
<title>Standard C++ Library ABI</title>
<link rel="StyleSheet" href="lib3styles.css" type="text/css" />
<link rel="Start" href="documentation.html" type="text/html"
title="GNU C++ Standard Library" />
<link rel="Copyright" href="17_intro/license.html" type="text/html" />
</head>
<body>
<h1 class="centered"><a name="top">C++ Standard Library ABI</a></h1>
<p class="fineprint"><em>
The latest version of this document is always available at
<a href="http://gcc.gnu.org/onlinedocs/libstdc++/abi.html">
http://gcc.gnu.org/onlinedocs/libstdc++/abi.html</a>.
</em></p>
<p><em>
To the <a href="http://gcc.gnu.org/libstdc++/">libstdc++-v3 homepage</a>.
</em></p>
<!-- ####################################################### -->
<hr />
<h3 class="left">
<a name="C++interface">The C++ interface</a>
</h3>
<p> C++ applications often dependent on specific language support
routines, say for throwing exceptions, or catching exceptions, and
perhaps also dependent on features in the C++ Standard Library.
</p>
<p> The C++ Standard Library has many include files, types defined in
those include files, specific named functions, and other behavior. The
text of these behaviors, as written in source include files, is called
the Application Programing Interface, or API.
</p>
<p> Furthermore, C++ source that is compiled into object files is
transformed by the compiler: it arranges objects with specific
alignment and in a particular layout, mangling names according to a
well-defined algorithm, has specific arrangements for the support of
virtual functions, etc. These details are defined as the compiler
Application Binary Interface, or ABI. The GNU C++ compiler uses an
industry-standard C++ ABI starting with version 3. Details can be
found in the <a href="http://www.codesourcery.com/cxx-abi/abi.html">
ABI specification</a>.
</p>
<p>
The GNU C++ compiler, g++, has a compiler command line option to
switch between various different C++ ABIs. This explicit version
switch is the flag <code> -fabi-version</code>. In addition, some
g++ command line options may change the ABI as a side-effect of
use. Such flags include <code>-fpack-struct</code> and
<code>-fno-exceptions</code>, but include others: see the complete
list in the GCC manual under the heading <a
href="http://gcc.gnu.org/onlinedocs/gcc/Code-Gen-Options.html#Code%20Gen%20Options">Options
for Code Generation Conventions</a>.
</p>
<p> The configure options used when building a specific libstdc++
version may also impact the resulting library ABI. The available
configure options, and their impact on the library ABI, are documented
<a href="http://gcc.gnu.org/onlinedocs/libstdc++/configopts.html">
here</a>.
</p>
<p> Putting all of these ideas together results in the C++ Standard
library ABI, which is the compilation of a given library API by a
given compiler ABI. In a nutshell:
</p>
<code> library API + compiler ABI = library ABI</code>
<p>
The library ABI is mostly of interest for end-users who have
unresolved symbols and are linking dynamically to the C++ Standard
library, and who thus must be careful to compile their application
with a compiler that is compatible with the available C++ Standard
library binary. In this case, compatible is defined with the equation
above: given an application compiled with a given compiler ABI and
library API, it will work correctly with a Standard C++ Library
created with the same constraints.
</p>
<p>
To use a specific version of the C++ ABI, one must use a
corresponding GNU C++ toolchain (Ie, g++ and libstdc++) that
implements the C++ ABI in question.
</p>
<h3 class="left">
<a name="ABI versioning">Versioning</a>
</h3>
<p> The C++ interface has evolved throughout the history of the GNU
C++ toolchain. With each release, various details have been changed so
as to give distinct versions to the C++ interface.
</p>
<h5 class="left">
<a name="goals">Goals of versioning</a>
</h5>
<p>Extending existing, stable ABIs. Versioning gives subsequent stable
releases series libraries the ability to add new symbols and add
functionality, all the while retaining backwards compatibility with
the previous releases in the series. Note: the reverse is not true. It
is not possible to take binaries linked with the latest version of a
release series (if symbols have been added) and expect the initial
release of the series to remain link compatible.
</p>
<p>Allows multiple, incompatible ABIs to coexist at the same time.
</p>
<p>
</p>
<h5 class="left">
<a name="details"> Version History </a>
</h5>
<p>
How can this complexity be managed? What does C++ versioning mean?
Because library and compiler changes often make binaries compiled
with one version of the GNU tools incompatible with binaries
compiled with other (either newer or older) versions of the same GNU
tools, specific techniques are used to make managing this complexity
easier.
</p>
<p>
The following techniques are used:
</p>
<ul>
<li> <p>Release versioning on the libgcc_s.so binary. This is
implemented via file names and the ELF DT_SONAME mechanism (at least
on ELF systems).</p>
<p>It is versioned as follows:
</p>
<ul>
<li>gcc-3.0.0: libgcc_s.so.1</li>
<li>gcc-3.0.1: libgcc_s.so.1</li>
<li>gcc-3.0.2: libgcc_s.so.1</li>
<li>gcc-3.0.3: libgcc_s.so.1</li>
<li>gcc-3.0.4: libgcc_s.so.1</li>
<li>gcc-3.1.0: libgcc_s.so.1</li>
<li>gcc-3.1.1: libgcc_s.so.1</li>
<li>gcc-3.2.0: libgcc_s.so.1</li>
<li>gcc-3.2.1: libgcc_s.so.1</li>
<li>gcc-3.2.2: libgcc_s.so.1</li>
<li>gcc-3.2.3: libgcc_s.so.1</li>
<li>gcc-3.3.0: libgcc_s.so.1</li>
<li>gcc-3.3.1: libgcc_s.so.1</li>
<li>gcc-3.3.2: libgcc_s.so.1</li>
<li>gcc-3.3.3: libgcc_s.so.1</li>
<li>gcc-3.4.0: libgcc_s.so.1</li>
</ul>
</li>
<p></p>
<li>Release versioning on the libstdc++.so binary, implemented in the same was as the libgcc_s.so binary, above.
<p>It is versioned as follows:
</p>
<ul>
<li>gcc-3.0.0: libstdc++.so.3.0.0</li>
<li>gcc-3.0.1: libstdc++.so.3.0.1</li>
<li>gcc-3.0.2: libstdc++.so.3.0.2</li>
<li>gcc-3.0.3: libstdc++.so.3.0.2 (Error should be libstdc++.so.3.0.3)</li>
<li>gcc-3.0.4: libstdc++.so.3.0.4</li>
<li>gcc-3.1.0: libstdc++.so.4.0.0</li>
<li>gcc-3.1.1: libstdc++.so.4.0.1</li>
<li>gcc-3.2.0: libstdc++.so.5.0.0</li>
<li>gcc-3.2.1: libstdc++.so.5.0.1</li>
<li>gcc-3.2.2: libstdc++.so.5.0.2</li>
<li>gcc-3.2.3: libstdc++.so.5.0.3 (Not strictly required)</li>
<li>gcc-3.3.0: libstdc++.so.5.0.4</li>
<li>gcc-3.3.1: libstdc++.so.5.0.5</li>
<li>gcc-3.3.2: libstdc++.so.5.0.5</li>
<li>gcc-3.3.3: libstdc++.so.5.0.5</li>
<li>gcc-3.4.0: libstdc++.so.6.0.0</li>
</ul>
</li>
<p></p>
<li>Symbol versioning on the libgcc_s.so binary.
<p>mapfile: gcc/libgcc-std.ver</p>
<p>It is versioned with the following labels and version definitions:</p>
<ul>
<li>gcc-3.0.0: GCC_3.0</li>
<li>gcc-3.0.1: GCC_3.0</li>
<li>gcc-3.0.2: GCC_3.0</li>
<li>gcc-3.0.3: GCC_3.0</li>
<li>gcc-3.0.4: GCC_3.0</li>
<li>gcc-3.1.0: GCC_3.0</li>
<li>gcc-3.1.1: GCC_3.0</li>
<li>gcc-3.2.0: GCC_3.0</li>
<li>gcc-3.2.1: GCC_3.0</li>
<li>gcc-3.2.2: GCC_3.0</li>
<li>gcc-3.2.3: GCC_3.0</li>
<li>gcc-3.3.0: GCC_3.0</li>
<li>gcc-3.3.1: GCC_3.0</li>
<li>gcc-3.3.2: GCC_3.0</li>
<li>gcc-3.3.3: GCC_3.0</li>
<li>gcc-3.4.0: GCC_3.0</li>
</ul>
</li>
<p></p>
<li>Symbol versioning on the libstdc++.so binary.
<p>mapfile: libstdc++-v3/config/linker-map.gnu</p>
<p>It is versioned with the following labels and version
definitions, where the version definition is the maximum for a
particular release. Note, only symbol which are newly introduced
will use the maximum version definition. Thus, for release series
with the same label, but incremented version definitions, the later
release has both versions. (An example of this would be the
gcc-3.2.1 release, which has GLIBCPP_3.2.1 for new symbols and
GLIBCPP_3.2 for symbols that were introduced in the gcc-3.2.0
release.)
</p>
<ul>
<li>gcc-3.0.0: (Error, not versioned)</li>
<li>gcc-3.0.1: (Error, not versioned)</li>
<li>gcc-3.0.2: (Error, not versioned)</li>
<li>gcc-3.0.3: (Error, not versioned)</li>
<li>gcc-3.0.4: (Error, not versioned)</li>
<li>gcc-3.1.0: GLIBCPP_3.1, CXXABI_1</li>
<li>gcc-3.1.1: GLIBCPP_3.1, CXXABI_1</li>
<li>gcc-3.2.0: GLIBCPP_3.2, CXXABI_1.2</li>
<li>gcc-3.2.1: GLIBCPP_3.2.1, CXXABI_1.2</li>
<li>gcc-3.2.2: GLIBCPP_3.2.2, CXXABI_1.2</li>
<li>gcc-3.2.3: GLIBCPP_3.2.2, CXXABI_1.2</li>
<li>gcc-3.3.0: GLIBCPP_3.2.2, CXXABI_1.2.1</li>
<li>gcc-3.3.1: GLIBCPP_3.2.3, CXXABI_1.2.1</li>
<li>gcc-3.3.2: GLIBCPP_3.2.3, CXXABI_1.2.1</li>
<li>gcc-3.3.3: GLIBCPP_3.2.3, CXXABI_1.2.1</li>
<li>gcc-3.4.0: GLIBCXX_3.4, CXXABI_1.3</li>
</ul>
</li>
<p></p>
<li>
<p>Incremental bumping of a compiler pre-defined macro,
__GXX_ABI_VERSION. This macro is defined as the version of the
compiler v3 ABI, with g++ 3.0.x being version 100. This macro will
be automatically defined whenever g++ is used (the curious can
test this by invoking g++ with the '-v' flag.)
</p>
<p>
This macro is defined in the file "lang-specs.h" in the gcc/cp directory.
Later versions define it in "c-common.c" in the gcc directory.
</p>
<p>
It is versioned as follows:
</p>
<ul>
<li>gcc-3.0.x: 100</li>
<li>gcc-3.1.x: 100 (Error, should be 101)</li>
<li>gcc-3.2.x: 102</li>
<li>gcc-3.3.x: 102</li>
<li>gcc-3.4.x: 1002</li>
</ul>
</li>
<p></p>
<li>
<p>Changes to the default compiler option for
<code>-fabi-version</code>.
</p>
<p>
It is versioned as follows:
</p>
<ul>
<li>gcc-3.0.x: (Error, not versioned) </li>
<li>gcc-3.1.x: (Error, not versioned) </li>
<li>gcc-3.2.x: <code>-fabi-version=1</code></li>
<li>gcc-3.3.x: <code>-fabi-version=1</code></li>
<li>gcc-3.4.x: <code>-fabi-version=2</code></li>
</ul>
</li>
<p></p>
<li>
<p>Incremental bumping of a library pre-defined macro. For releases
before 3.4.0, the macro is __GLIBCPP__. For later releases, it's
__GLIBCXX__. (The libstdc++ project generously changed from CPP to
CXX throughout its source to allow the "C" pre-processor the CPP
macro namespace.) These macros are defined as the date the library
was released, in compressed ISO date format, as an unsigned long.
</p>
<p>
In addition, the pre-defined macro is defined in the file
"c++config" in the "libstdc++-v3/include/bits" directory and is
changed every night by an automated script.
</p>
<p>
It is versioned as follows:
</p>
<ul>
<li>gcc-3.0.0: 20010615</li>
<li>gcc-3.0.1: 20010819</li>
<li>gcc-3.0.2: 20011023</li>
<li>gcc-3.0.3: 20011220</li>
<li>gcc-3.0.4: 20020220</li>
<li>gcc-3.1.0: 20020514</li>
<li>gcc-3.1.1: 20020725</li>
<li>gcc-3.2.0: 20020814</li>
<li>gcc-3.2.1: 20021119</li>
<li>gcc-3.2.2: 20030205</li>
<li>gcc-3.2.3: 20030422</li>
<li>gcc-3.3.0: 20030513</li>
<li>gcc-3.3.1: 20030804</li>
<li>gcc-3.3.2: 20031016</li>
<li>gcc-3.3.3: 20040214</li>
<li>gcc-3.4.0: 20040419</li>
</ul>
</li>
<p></p>
<li>
<p>
Incremental bumping of a library pre-defined macro,
_GLIBCPP_VERSION. This macro is defined as the released version of
the library, as a string literal. This is only implemented in
gcc-3.1.0 releases and higher, and is deprecated in 3.4.
</p>
<p>
This macro is defined in the file "c++config" in the
"libstdc++-v3/include/bits" directory and is generated
automatically by autoconf as part of the configure-time generation
of config.h.
</p>
<p>
It is versioned as follows:
</p>
<ul>
<li>gcc-3.0.0: "3.0.0"</li>
<li>gcc-3.0.1: "3.0.0" (Error, should be "3.0.1")</li>
<li>gcc-3.0.2: "3.0.0" (Error, should be "3.0.2")</li>
<li>gcc-3.0.3: "3.0.0" (Error, should be "3.0.3")</li>
<li>gcc-3.0.4: "3.0.0" (Error, should be "3.0.4")</li>
<li>gcc-3.1.0: "3.1.0"</li>
<li>gcc-3.1.1: "3.1.1"</li>
<li>gcc-3.2.0: "3.2"</li>
<li>gcc-3.2.1: "3.2.1"</li>
<li>gcc-3.2.2: "3.2.2"</li>
<li>gcc-3.2.3: "3.2.3"</li>
<li>gcc-3.3.0: "3.3"</li>
<li>gcc-3.3.1: "3.3.1"</li>
<li>gcc-3.3.2: "3.3.2"</li>
<li>gcc-3.3.3: "3.3.3"</li>
<li>gcc-3.4.0: "version-unused"</li>
</ul>
</li>
<p></p>
<li>
<p>
Matching each specific C++ compiler release to a specific set of
C++ include files. This is only implemented in gcc-3.1.1 releases
and higher.
</p>
<p>
All C++ includes are installed in include/c++, then nest in a
directory hierarchy corresponding to the C++ compiler's released
version. This version corresponds to the variable "gcc_version" in
"libstdc++-v3/acinclude.m4," and more details can be found in that
file's macro GLIBCPP_CONFIGURE.
</p>
<p>
C++ includes are versioned as follows:
</p>
<ul>
<li>gcc-3.0.0: include/g++-v3</li>
<li>gcc-3.0.1: include/g++-v3</li>
<li>gcc-3.0.2: include/g++-v3</li>
<li>gcc-3.0.3: include/g++-v3</li>
<li>gcc-3.0.4: include/g++-v3</li>
<li>gcc-3.1.0: include/g++-v3</li>
<li>gcc-3.1.1: include/c++/3.1.1</li>
<li>gcc-3.2.0: include/c++/3.2</li>
<li>gcc-3.2.1: include/c++/3.2.1</li>
<li>gcc-3.2.2: include/c++/3.2.2</li>
<li>gcc-3.2.3: include/c++/3.2.3</li>
<li>gcc-3.3.0: include/c++/3.3</li>
<li>gcc-3.3.1: include/c++/3.3.1</li>
<li>gcc-3.3.2: include/c++/3.3.2</li>
<li>gcc-3.3.3: include/c++/3.3.3</li>
<li>gcc-3.4.0: include/c++/3.4.0</li>
</ul>
</li>
<p></p>
</ul>
<p>
Taken together, these techniques can accurately specify interface
and implementation changes in the GNU C++ tools themselves. Used
properly, they allow both the GNU C++ tools implementation, and
programs using them, an evolving yet controlled development that
maintains backward compatibility.
</p>
<h5 class="left">
<a name="requirements"> Minimum requirements for a versioned ABI </a>
</h5>
<p>
Minimum environment that supports a versioned ABI: A supported
dynamic linker, a GNU linker of sufficient vintage to understand
demangled C++ name globbing (ld), a shared executable compiled with
g++, and shared libraries (libgcc_s, libstdc++-v3) compiled by a
compiler (g++) with a compatible ABI. Phew.
</p>
<p>
On top of all that, an additional constraint: libstdc++ did not
attempt to version symbols (or age gracefully, really) until version
3.1.0.
</p>
<p>
Most modern Linux and BSD versions, particularly ones using
gcc-3.1.x tools and more recent vintages, will meet the requirements above.
</p>
<h5 class="left">
<a name="config"> What configure options impact symbol versioning? </a>
</h5>
<p>
It turns out that most of the configure options that change default
behavior will impact the mangled names of exported symbols, and thus
impact versioning and compatibility.
</p>
</p>
For more information on configure options, including ABI impacts, see:
http://gcc.gnu.org/onlinedocs/libstdc++/configopts.html
</p>
<p>
There is one flag that explicitly deals with symbol versioning:
--enable-symvers.
</p>
<p>
In particular, libstdc++-v3/acinclude.m4 has a macro called
GLIBCXX_ENABLE_SYMVERS that defaults to yes (or the argument passed
in via --enable-symvers=foo). At that point, the macro attempts to
make sure that all the requirement for symbol versioning are in
place. For more information, please consult acinclude.m4.
</p>
<h5 class="left">
<a name="active"> How to tell if symbol versioning is, indeed, active? </a>
</h5>
<p>
When the GNU C++ library is being built with symbol versioning on,
you should see the following at configure time for libstdc++-v3:
</p>
<code> checking versioning on shared library symbols... gnu</code>
<p>
If you don't see this line in the configure output, or if this line
appears but the last word is 'no', then you are out of luck.
</p>
<p>
If the compiler is pre-installed, a quick way to test is to compile
the following (or any) simple C++ file and link it to the shared
libstdc++ library:
</p>
<pre>
#include &lt;iostream&gt;
int main()
{ std::cout &lt;&lt; "hello" &lt;&lt; std::endl; return 0; }
%g++ hello.cc -o hello.out
%ldd hello.out
libstdc++.so.5 => /usr/lib/libstdc++.so.5 (0x00764000)
libm.so.6 => /lib/tls/libm.so.6 (0x004a8000)
libgcc_s.so.1 => /mnt/hd/bld/gcc/gcc/libgcc_s.so.1 (0x40016000)
libc.so.6 => /lib/tls/libc.so.6 (0x0036d000)
/lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x00355000)
%nm hello.out
</pre>
<p>
If you see symbols in the resulting output with "GLIBCXX_3" as part
of the name, then the executable is versioned. Here's an example:
</p>
<code> U _ZNSt8ios_base4InitC1Ev@@GLIBCXX_3.4 </code>
<h3 class="left">
<a name="ABI allowed">Library allowed ABI changes</a>
</h3>
<p>
The following will cause the library minor version number to
increase, say from "libstdc++.so.3.0.4" to "libstdc++.so.3.0.5".
</p>
<ul>
<li>adding an exported global or static data member</li>
<li>adding an exported function, static or non-virtual member function</li>
<li>adding an exported symbol or symbols by additional instantiations</li>
</ul>
<p>
</p>
<p>
Other allowed changes are possible.
</p>
<h3 class="left">
<a name="ABI disallowed">Library disallowed ABI changes</a>
</h3>
<p>
The following non-exhaustive list will cause the library major version
number to increase, say from "libstdc++.so.3.0.4" to
"libstdc++.so.4.0.0".
</p>
<ul>
<li>changes in the gcc/g++ compiler ABI</li>
<li>changing size of an exported symbol</li>
<li>changing alignment of an exported symbol</li>
<li>changing the layout of an exported symbol</li>
<li>changing mangling on an exported symbol</li>
<li>deleting an exported symbol</li>
<li>changing the inheritance properties of a type by adding or removing
base classes</li>
<li>
changing the size, alignment, or layout of types
specified in the C++ standard. These may not necessarily be
instantiated or otherwise exported in the library binary, and
include all the required locale facets, as well as things like
std::basic_streambuf, et al.
</li>
</ul>
<h3 class="left">
<a name="implementation">Library implementation strategy</a>
</h3>
<ul>
<li>Separation of interface and implementation</li>
<p>This is accomplished by two techniques that separate the API from
the ABI: forcing undefined references to link against a library binary
for definitions.
</p>
<ul>
<li>Include files have declarations, source files have defines</li>
<p> For non-templatized types, such as much of <code>class
locale</code>, the appropriate standard C++ include, say
<code>locale</code>, can contain full declarations, while various
source files (say <code> locale.cc, locale_init.cc,
localename.cc</code>) contain definitions.</p>
<li>Extern template on required types</li>
<p>For parts of the standard that have an explicit list of required
instantiations, the GNU extension syntax <code> extern template
</code> can be used to control where template definitions
reside. By marking required instantiations as <code> extern
template </code> in include files, and providing explicit
instantiations in the appropriate instantiation files, non-inlined
template functions can be versioned. This technique is mostly used
on parts of the standard that require <code> char</code> and <code>
wchar_t</code> instantiations, and includes <code>
basic_string</code>, the locale facets, and the types in <code>
iostreams</code>.</p>
</ul>
<p> In addition, these techniques have the additional benefit that
they reduce binary size, which can increase runtime performance.
</p>
<li>Namespaces linking symbol definitions to export mapfiles</li>
<p>All symbols in the shared library binary are processed by a linker
script at build time that either allows or disallows external
linkage. Because of this, some symbols, regardless of normal C/C++
linkage, are not visible. Symbols that are internal have several
appealing characteristics: by not exporting the symbols, there are no
relocations when the shared library is started and thus this makes for
faster runtime loading performance by the underlying dynamic loading
mechanism. In addition, they have the possibility of changing without
impacting ABI compatibility.
</p>
<p>The following namespaces are transformed by the mapfile:</p>
<ul>
<li><code>namespace std</code></li>
<p> Defaults to exporting all symbols in label
<code>GLIBCXX</code> that do not begin with an underscore, ie
<code>__test_func</code> would not be exported by default. Select
exceptional symbols are allowed to be visible.</p>
<li><code>namespace __gnu_cxx</code></li>
<p> Defaults to not exporting any symbols in label
<code>GLIBCXX</code>, select items are allowed to be visible.</p>
<li><code>namespace __gnu_internal</code></li>
<p> Defaults to not exported, no items are allowed to be visible.</p>
<li><code>namespace __cxxabiv1</code>, aliased to <code> namespace abi</code></li>
<p> Defaults to not exporting any symbols in label
<code>CXXABI</code>, select items are allowed to be visible.</p>
</ul>
<p>
</p>
<li>Freezing the API</li>
<p>Disallowed changes, as above, are not made on a stable release
branch. Enforcement tends to be less strict with GNU extensions that
standard includes.</p> </ul>
<h3 class="left">
<a name="ABI testing">Testing ABI changes</a>
</h3>
<p>
Testing for GNU C++ ABI changes is composed of two distinct areas:
testing the C++ compiler (g++) for compiler changes, and testing the
C++ library (libstdc++) for library changes.
</p>
<p>
Testing the C++ compiler ABI can be done various ways.
</p>
<p>
One.
Intel ABI checker. More information can be obtained
<a href="http://developer.intel.com/software/products/opensource/">here.</a>
</p>
<p>
Two.
The second is yet unreleased, but has been announced on the gcc
mailing list. It is yet unspecified if these tools will be freely
available, and able to be included in a GNU project. Please contact
Mark Mitchell (mark@codesourcery.com) for more details, and current
status.
</p>
<p>
Three.
Involves using the vlad.consistency test framework. This has also been
discussed on the gcc mailing lists.
</p>
<p>
Testing the C++ library ABI can also be done various ways.
</p>
<p>
One.
(Brendan Kehoe, Jeff Law suggestion to run 'make check-c++' two ways,
one with a new compiler and an old library, and the other with an old
compiler and a new library, and look for testsuite regressions)
</p>
<p>
Details on how to set this kind of test up can be found here:
http://gcc.gnu.org/ml/gcc/2002-08/msg00142.html
</p>
<p>
Two.
Use the 'make check-abi' rule in the libstdc++-v3 Makefile.
</p>
<p>
This is a proactive check the library ABI. Currently, exported symbol
names that are either weak or defined are checked against a last known
good baseline. Currently, this baseline is keyed off of 3.2.0
binaries, as this was the last time the .so number was incremented. In
addition, all exported names are demangled, and the exported objects
are checked to make sure they are the same size as the same object in
the baseline.
</p>
<p>
This dataset is insufficient, yet a start. Also needed is a
comprehensive check for all user-visible types part of the standard
library for sizeof() and alignof() changes.
</p>
<p>
Verifying compatible layouts of objects is not even attempted. It
should be possible to use sizeof, alignof, and offsetof to compute
offsets for each structure and type in the standard library, saving to
another datafile. Then, compute this in a similar way for new
binaries, and look for differences.
</p>
<p>
Another approach might be to use the -fdump-class-hierarchy flag to
get information. However, currently this approach gives insufficient
data for use in library testing, as class data members, their offsets,
and other detailed data is not displayed with this flag.
(See g++/7470 on how this was used to find bugs.)
</p>
<p>
Perhaps there are other C++ ABI checkers. If so, please notify
us. We'd like to know about them!
</p>
<h3 class="left">
<a name="ABI multi testing">Testing Multi-ABI binaries</a>
</h3>
<p>
A "C" application, dynamically linked to two shared libraries, liba,
libb. The dependent library liba is C++ shared library compiled with
gcc-3.3.x, and uses io, exceptions, locale, etc. The dependent library
libb is a C++ shared library compiled with gcc-3.4.x, and also uses io,
exceptions, locale, etc.
</p>
<p> As above, libone is constructed as follows: </p>
<pre>
%$bld/H-x86-gcc-3.4.0/bin/g++ -fPIC -DPIC -c a.cc
%$bld/H-x86-gcc-3.4.0/bin/g++ -shared -Wl,-soname -Wl,libone.so.1 -Wl,-O1 -Wl,-z,defs a.o -o libone.so.1.0.0
%ln -s libone.so.1.0.0 libone.so
%$bld/H-x86-gcc-3.4.0/bin/g++ -c a.cc
%ar cru libone.a a.o
</pre>
<p> And, libtwo is constructed as follows: </p>
<pre>
%$bld/H-x86-gcc-3.3.3/bin/g++ -fPIC -DPIC -c b.cc
%$bld/H-x86-gcc-3.3.3/bin/g++ -shared -Wl,-soname -Wl,libtwo.so.1 -Wl,-O1 -Wl,-z,defs b.o -o libtwo.so.1.0.0
%ln -s libtwo.so.1.0.0 libtwo.so
%$bld/H-x86-gcc-3.3.3/bin/g++ -c b.cc
%ar cru libtwo.a b.o
</pre>
<p> ...with the resulting libraries looking like </p>
<pre>
%ldd libone.so.1.0.0
libstdc++.so.6 => /usr/lib/libstdc++.so.6 (0x40016000)
libm.so.6 => /lib/tls/libm.so.6 (0x400fa000)
libgcc_s.so.1 => /mnt/hd/bld/gcc/gcc/libgcc_s.so.1 (0x4011c000)
libc.so.6 => /lib/tls/libc.so.6 (0x40125000)
/lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x00355000)
%ldd libtwo.so.1.0.0
libstdc++.so.5 => /usr/lib/libstdc++.so.5 (0x40027000)
libm.so.6 => /lib/tls/libm.so.6 (0x400e1000)
libgcc_s.so.1 => /mnt/hd/bld/gcc/gcc/libgcc_s.so.1 (0x40103000)
libc.so.6 => /lib/tls/libc.so.6 (0x4010c000)
/lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x00355000)
</pre>
<p> Then, the "C" compiler is used to compile a source file that uses
functions from each library.</p>
<pre>
gcc test.c -g -O2 -L. -lone -ltwo /usr/lib/libstdc++.so.5 /usr/lib/libstdc++.so.6
</pre>
<p>
Which gives the expected:
</p>
<pre>
%ldd a.out
libstdc++.so.5 => /usr/lib/libstdc++.so.5 (0x00764000)
libstdc++.so.6 => /usr/lib/libstdc++.so.6 (0x40015000)
libc.so.6 => /lib/tls/libc.so.6 (0x0036d000)
libm.so.6 => /lib/tls/libm.so.6 (0x004a8000)
libgcc_s.so.1 => /mnt/hd/bld/gcc/gcc/libgcc_s.so.1 (0x400e5000)
/lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x00355000)
</pre>
<p>
This resulting binary, when executed, will be able to safely use code
from both liba, and the dependent libstdc++.so.6, and libb, with the
dependent libstdc++.so.5.
</p>
<h3 class="left">
<a name="references">Bibliography / Further Reading</a>
</h3>
<p>
ABIcheck, a vague idea of checking ABI compatibility
http://abicheck.sourceforge.net/
<p>
C++ ABI reference
http://www.codesourcery.com/cxx-abi/
</p>
<p>
Intel ABI documentation
"Intel® Compilers for Linux* -Compatibility with the GNU Compilers"
(included in icc 6.0)
</p>
<p>
Sun Solaris 2.9 docs
Linker and Libraries Guide (document 816-1386)
C++ Migration Guide (document 816-2459)
http://docs.sun.com/db/prod/solaris.9
http://docs.sun.com/?p=/doc/816-1386&a=load
</p>
<p>
Ulrich Drepper, "ELF Symbol Versioning"
http://people.redhat.com/drepper/symbol-versioning
</p>

View File

@ -1,389 +0,0 @@
2002-10-14 Benjamin Kosnik
Description of the libstdc++ ABI.
I. What is an ABI? What's covered? What's not?
- scope of document, of use to system integrators.
- What's the deal with C++? Why can't different compiler's object
files link with each other? Bug? Feature?
- compilation includes and linked library binary must match up..
- shared library only, static is immutable.
- What's an ABI?
- library ABI, compiler ABI different issues, (but related)
- GNU C++ does not have a compiler command line option to switch
between various different C++ ABIs. For instance, there is no way to
switch between the gcc-3.0.x ABI, gcc-3.1.x ABI, and the gcc-3.2.x
ABI during compilation. Other C++ compilers do allow this, and some
g++ command line options may change the ABI (-fno-exceptions, see
the complete list), but there is no version switch. Sorry.
To use a specific C++ABI, one must use the corresponding GNU C++
toolchain.
- How can this complexity be managed? What does C++ versioning mean?
Because library and compiler changes often make binaries compiled
with one version of the GNU tools incompatible with binaries
compiled with other (either newer or older) versions of the same GNU
tools, specific techniques are used to make managing this complexity
easier.
The following techniques are used:
- Release versioning on the libgcc_s.so binary.
It is versioned as follows:
gcc-3.0.0: libgcc_s.so.1
gcc-3.0.1: libgcc_s.so.1
gcc-3.0.2: libgcc_s.so.1
gcc-3.0.3: libgcc_s.so.1
gcc-3.0.4: libgcc_s.so.1
gcc-3.1.0: libgcc_s.so.1
gcc-3.1.1: libgcc_s.so.1
gcc-3.2.0: libgcc_s.so.1
- Release versioning on the libstdc++.so binary.
It is versioned as follows:
gcc-3.0.0: libstdc++.so.3.0.0
gcc-3.0.1: libstdc++.so.3.0.1
gcc-3.0.2: libstdc++.so.3.0.2
gcc-3.0.3: libstdc++.so.3.0.2 (Error, should be libstdc++.so.3.0.3)
gcc-3.0.4: libstdc++.so.3.0.4
gcc-3.1.0: libstdc++.so.4.0.0
gcc-3.1.1: libstdc++.so.4.0.1
gcc-3.2.0: libstdc++.so.5.0.0
- Symbol versioning on the libgcc_s.so binary.
file: gcc/libgcc-std.ver
It is versioned as follows:
gcc-3.0.0: GCC_3.0
gcc-3.0.1: GCC_3.0
gcc-3.0.2: GCC_3.0
gcc-3.0.3: GCC_3.0
gcc-3.0.4: GCC_3.0
gcc-3.1.0: GCC_3.0
gcc-3.1.1: GCC_3.0
gcc-3.2.0: GCC_3.0
- Symbol versioning on the libstdc++.so binary.
It is versioned as follows:
gcc-3.0.0: (Error, unversioned)
gcc-3.0.1: (Error, unversioned)
gcc-3.0.2: (Error, unversioned)
gcc-3.0.3: (Error, unversioned)
gcc-3.0.4: (Error, unversioned)
gcc-3.1.0: GLIBCPP_3.1, CXXABI_1
gcc-3.1.1: GLIBCPP_3.1, CXXABI_1
gcc-3.2.0: GLIBCPP_3.2, CXXABI_1.2
file: libstdc++-v3/config/linker-map.gnu
- Incremental bumping of a compiler pre-defined macro,
__GXX_ABI_VERSION. This macro is defined as the version of the
compiler v3 ABI, with g++ 3.0.x being version 100. This macro will
be automatically defined whenever g++ is used (the curious can
test this by invoking g++ with the '-v' flag.)
This macro is defined in the file "lang-specs.h" in the gcc/cp directory.
Later versions define it in "c-common.c" in the gcc directory.
It is versioned as follows:
gcc-3.0.x: 100
gcc-3.1.x: 100 (Error, should be 101)
gcc-3.2.x: 102
- Incremental bumping of a library pre-defined macro, __GLIBCPP__ or
__GLIBCXX__. This macro is defined as the date the library was
released, in compressed ISO date format, as an unsigned long.
This macro is defined in the file "c++config" in the
"libstdc++-v3/include/bits" directory and is changed every night
by an automated script.
It is versioned as follows:
gcc-3.0.0: 20010615
gcc-3.0.1: 20010819
gcc-3.0.2: 20011023
gcc-3.0.3: 20011220
gcc-3.0.4: 20020220
gcc-3.1.0: 20020514
gcc-3.1.1: 20020725
gcc-3.2.0: 20020814
- Incremental bumping of a library pre-defined macro,
_GLIBCPP_VERSION. This macro is defined as the released version of
the library, as a string literal. This is only implemented in
gcc-3.1.0 releases and higher, and changed to _GLIBCXX_VERSION in 3.4.
This macro is defined in the file "c++config" in the
"libstdc++-v3/include/bits" directory and is generated
automatically by autoconf as part of the configure-time generation
of config.h.
It is versioned as follows:
gcc-3.0.0: "3.0.0"
gcc-3.0.1: "3.0.0" (Error, should be "3.0.1")
gcc-3.0.2: "3.0.0" (Error, should be "3.0.2")
gcc-3.0.3: "3.0.0" (Error, should be "3.0.3")
gcc-3.0.4: "3.0.0" (Error, should be "3.0.4")
gcc-3.1.0: "3.1.0"
gcc-3.1.1: "3.1.1"
gcc-3.2.0: "3.2"
- Matching each specific C++ compiler release to a specific set of
C++ include files. This is only implemented in gcc-3.1.1 releases
and higher.
All C++ includes are installed in include/c++, then nest in a
directory hierarchy corresponding to the C++ compiler's released
version. This version corresponds to the variable "gcc_version" in
"libstdc++-v3/acinclude.m4," and more details can be found in that
file's macro GLIBCPP_CONFIGURE.
C++ includes are versioned as follows:
gcc-3.0.0: include/g++-v3
gcc-3.0.1: include/g++-v3
gcc-3.0.2: include/g++-v3
gcc-3.0.3: include/g++-v3
gcc-3.0.4: include/g++-v3
gcc-3.1.0: include/g++-v3
gcc-3.1.1: include/c++/3.1.1
gcc-3.2.0: include/c++/3.2
Taken together, these techniques can accurately specify interface
and implementation changes in the GNU C++ tools themselves. Used
properly, they allow both the GNU C++ tools implementation, and
programs using them, an evolving yet controlled development that
maintains backward compatibility.
- Minimum environment that supports a versioned ABI: what's needed? A
supported dynamic linker, a GNU linker of sufficient vintage to
understand demangled C++ name globbing (ld), a shared executable
compiled with g++, and shared libraries (libgcc_s, libstdc++-v3)
compiled by a compiler (g++) with a compatible ABI. Phew.
On top of all that, an additional constraint: libstdc++ did not
attempt to version symbols (or age gracefully, really) until version
3.1.0.
Most modern Linux and BSD versions, particularly ones using
gcc-3.1.x tools, will meet the requirements above.
- What configure options impact symbol versioning?
It turns out that most of the configure options that change default
behavior will impact the mangled names of exported symbols, and thus
impact versioning and compatibility.
For more information on configure options, including ABI impacts, see:
http://gcc.gnu.org/onlinedocs/libstdc++/configopts.html
There is one flag that explicitly deals with symbol versioning:
--enable-symvers.
In particular, libstdc++-v3/acinclude.m4 has a macro called
GLIBCXX_ENABLE_SYMVERS that defaults to yes (or the argument passed
in via --enable-symvers=foo). At that point, the macro attempts to
make sure that all the requirement for symbol versioning are in
place. For more information, please consult acinclude.m4.
- How can I tell if symbol versioning is, indeed, active?
When the GNU C++ library is being built with symbol versioning on,
you should see the following at configure time for libstdc++-v3:
checking versioning on shared library symbols... gnu
If you don't see this line in the configure output, or if this line
appears but the last word is 'no', then you are out of luck.
If the compiler is pre-installed, a quick way to test is to compile
the following (or any) simple C++ file:
#include <iostream>
int main()
{ std::cout << "hello" << std::endl; return 0; }
%g++ hello.cc -o hello.out
%nm hello.out
If you see symbols in the resulting output with "GLIBCPP_3.x" as part
of the name, then the executable is versioned. Here's an example:
U _ZNSt8ios_base4InitC1Ev@@GLIBCPP_3.1
II. Library ABI changes
The following will cause the library major version number to
increase, say from "libstdc++.so.3.0.4" to "libstdc++.so.4.0.0".
- (anything) changing in the gcc/g++ compiler ABI
- (anything) changing size of an exported symbol
- (anything) changing alignment of an exported symbol
- (anything) changing the layout of an exported symbol
- (anything) changing mangling on an exported symbol
- (anything) deleting an exported symbol
- (anything) changing the size, alignment, or layout of types
specified in the C++ standard. These may not necessarily be
instantiated or otherwise exported in the library binary, and
include all the required locale facets, as well as things like
std::basic_streambuf, et al.
Note: adding an exported symbol, if it's in a new and dependent
interface name, is ok.
The following will cause the library revision version number to
increase, say from "libstdc++.so.5.0.0" to "libstdc++.so.5.0.1".
- any release of the gcc toolchain.
III. Versioning
- include files
- versioning headers with version, why necessary
(need to control member/non-member functions, add delete files)
- shared library binaries
- release versions
- libtool versions
- when does so version get a bump? what are the options?
- how is the link map used?
- in an non-abi breaking minor release, how are symbols added?
removed?
- in an abi-breaking major release, what happens? symbol fall back
IV. Testing ABI changes
Testing for GNU C++ ABI changes is composed of two distinct areas:
testing the C++ compiler (g++) for compiler changes, and testing the
C++ library (libstdc++) for library changes.
Testing the C++ compiler ABI can be done various ways.
One.
Intel ABI checker. More information can be obtained
<a href="http://developer.intel.com/software/products/opensource/">here.</a>
Two.
The second is yet unreleased, but has been announced on the gcc
mailing list. It is yet unspecified if these tools will be freely
available, and able to be included in a GNU project. Please contact
Mark Mitchell (mark@codesourcery.com) for more details, and current
status.
Three.
Involves using the vlad.consistency test framework. This has also been
discussed on the gcc mailing lists.
Testing the C++ library ABI can also be done various ways.
One.
(Brendan Kehoe, Jeff Law suggestion to run 'make check-c++' two ways,
one with a new compiler and an old library, and the other with an old
compiler and a new library, and look for testsuite regressions)
Details on how to set this kind of test up can be found here:
http://gcc.gnu.org/ml/gcc/2002-08/msg00142.html
Two.
Use the 'make check-abi' rule in the libstdc++-v3 Makefile.
This is a proactive check the library ABI. Currently, exported symbol
names that are either weak or defined are checked against a last known
good baseline. Currently, this baseline is keyed off of 3.2.0
binaries, as this was the last time the .so number was incremented. In
addition, all exported names are demangled, and the exported objects
are checked to make sure they are the same size as the same object in
the baseline.
This dataset is insufficient, yet a start. Also needed is a
comprehensive check for all user-visible types part of the standard
library for sizeof() and alignof() changes.
Verifying compatible layouts of objects is not even attempted. It
should be possible to use sizeof, alignof, and offsetof to compute
offsets for each structure and type in the standard library, saving to
another datafile. Then, compute this in a similar way for new
binaries, and look for differences.
Another approach might be to use the -fdump-class-hierarchy flag to
get information. However, currently this approach gives insufficient
data for use in library testing, as class data members, their offsets,
and other detailed data is not displayed with this flag.
(See g++/7470 on how this was used to find bugs.)
Perhaps there are other C++ ABI checkers. If so, please notify
us. We'd like to know about them!
V. Issues not directly addressed, and possible suggestions
- what to do about multi-ABI systems (nathan scenario)?
- compatibility libs
--enable-version-specific-runtime-libs
- Alexandre Oliva proposal to have extended name attributes, modify ld
- directory-level versioning
- wrapping C++ API's in "C" to use the C ABI.
V. References
ABIcheck, a vague idea of checking ABI compatibility
http://abicheck.sourceforge.net/
C++ ABI reference
http://www.codesourcery.com/cxx-abi/
Intel ABI documentation
"Intel® Compilers for Linux* -Compatibility with the GNU Compilers"
(included in icc 6.0)
Sun Solaris 2.9 docs
Linker and Libraries Guide (document 816-1386)
C++ Migration Guide (document 816-2459)
http://docs.sun.com/db/prod/solaris.9
http://docs.sun.com/?p=/doc/816-1386&a=load
Ulrich Drepper, "ELF Symbol Versioning"
http://people.redhat.com/drepper/symbol-versioning

View File

@ -30,7 +30,7 @@
<ul>
<li><a href="17_intro/COPYING">License</a>
- GPL v2 license terms</li>
<li><a href="abi.txt">ABI Policy and Guidelines</a></li>
<li><a href="abi.html">ABI Policy and Guidelines</a></li>
<li><a href="17_intro/BUGS">BUGS</a></li>
<li><a href="17_intro/PROBLEMS">PROBLEMS</a>
- target-specific known issues</li>

View File

@ -63,9 +63,8 @@
namespace std
{
/// pair holds two objects of arbitrary type.
template <class _T1, class _T2>
template<class _T1, class _T2>
struct pair
{
typedef _T1 first_type; ///< @c first_type is the first bound type
@ -79,51 +78,51 @@ namespace std
/** The default constructor creates @c first and @c second using their
* respective default constructors. */
pair()
: first(), second() {}
: first(), second() { }
/** Two objects may be passed to a @c pair constructor to be copied. */
pair(const _T1& __a, const _T2& __b)
: first(__a), second(__b) {}
: first(__a), second(__b) { }
/** There is also a templated copy ctor for the @c pair class itself. */
template <class _U1, class _U2>
template<class _U1, class _U2>
pair(const pair<_U1, _U2>& __p)
: first(__p.first), second(__p.second) {}
: first(__p.first), second(__p.second) { }
};
/// Two pairs of the same type are equal iff their members are equal.
template <class _T1, class _T2>
template<class _T1, class _T2>
inline bool
operator==(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
{ return __x.first == __y.first && __x.second == __y.second; }
/// <http://gcc.gnu.org/onlinedocs/libstdc++/20_util/howto.html#pairlt>
template <class _T1, class _T2>
template<class _T1, class _T2>
inline bool
operator<(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
{ return __x.first < __y.first
|| (!(__y.first < __x.first) && __x.second < __y.second); }
/// Uses @c operator== to find the result.
template <class _T1, class _T2>
template<class _T1, class _T2>
inline bool
operator!=(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
{ return !(__x == __y); }
/// Uses @c operator< to find the result.
template <class _T1, class _T2>
template<class _T1, class _T2>
inline bool
operator>(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
{ return __y < __x; }
/// Uses @c operator< to find the result.
template <class _T1, class _T2>
template<class _T1, class _T2>
inline bool
operator<=(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
{ return !(__y < __x); }
/// Uses @c operator< to find the result.
template <class _T1, class _T2>
template<class _T1, class _T2>
inline bool
operator>=(const pair<_T1, _T2>& __x, const pair<_T1, _T2>& __y)
{ return !(__x < __y); }
@ -138,18 +137,11 @@ namespace std
* but LWG issue #181 says they should be passed by const value. We follow
* the LWG by default.
*/
template <class _T1, class _T2>
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// 181. make_pair() unintended behavior
inline pair<_T1, _T2>
make_pair(_T1 __x, _T2 __y)
{ return pair<_T1, _T2>(__x, __y); }
template<class _T1, class _T2>
inline pair<_T1, _T2>
make_pair(_T1 __x, _T2 __y) { return pair<_T1, _T2>(__x, __y); }
} // namespace std
#endif /* _PAIR_H */
// Local Variables:
// mode:C++
// End:

View File

@ -39,18 +39,14 @@ GLIBCXX_DIR=${glibcxx_builddir}/src/.libs
CXXLINK = \
$(LIBTOOL) --tag=CXX --mode=link $(CXX) \
-R $(GLIBGCC_DIR) -R $(GLIBCXX_DIR) \
$(AM_CXXFLAGS) $(CXXFLAGS) $(LDFLAGS) -o $@
# Generated lists of files to run. All of these names are valid make
# targets, if you wish to generate a list manually.
lists_of_files = \
testsuite_files \
testsuite_files_interactive \
testsuite_files_performance
$(AM_CXXFLAGS) $(CXXFLAGS) $(LDFLAGS) -lv3test -L. -o $@
## Build support library.
noinst_LIBRARIES = libv3test.a
libv3test_a_SOURCES = testsuite_hooks.cc testsuite_allocator.cc
libv3test_a_SOURCES = \
testsuite_abi.cc \
testsuite_allocator.cc \
testsuite_hooks.cc
## Build support utilities.
if GLIBCXX_TEST_ABI
@ -59,6 +55,7 @@ else
noinst_PROGRAMS =
endif
abi_check_SOURCES = abi_check.cc
abi_check_DEPENDENCIES = libv3test.a
all-local: stamp_wchar testsuite_files
@ -70,6 +67,14 @@ else
stamp_wchar:
endif
# Generated lists of files to run. All of these names are valid make
# targets, if you wish to generate a list manually.
lists_of_files = \
testsuite_files \
testsuite_files_interactive \
testsuite_files_performance
# We need more things in site.exp, but automake completely controls the
# creation of that file; there's no way to append to it without messing up
# the dependancy chains. So we overrule automake. This rule is exactly

View File

@ -58,8 +58,8 @@ ARFLAGS = cru
LIBRARIES = $(noinst_LIBRARIES)
libv3test_a_AR = $(AR) $(ARFLAGS)
libv3test_a_LIBADD =
am_libv3test_a_OBJECTS = testsuite_hooks.$(OBJEXT) \
testsuite_allocator.$(OBJEXT)
am_libv3test_a_OBJECTS = testsuite_abi.$(OBJEXT) \
testsuite_allocator.$(OBJEXT) testsuite_hooks.$(OBJEXT)
libv3test_a_OBJECTS = $(am_libv3test_a_OBJECTS)
PROGRAMS = $(noinst_PROGRAMS)
am_abi_check_OBJECTS = abi_check.$(OBJEXT)
@ -272,8 +272,16 @@ GLIBCXX_DIR = ${glibcxx_builddir}/src/.libs
CXXLINK = \
$(LIBTOOL) --tag=CXX --mode=link $(CXX) \
-R $(GLIBGCC_DIR) -R $(GLIBCXX_DIR) \
$(AM_CXXFLAGS) $(CXXFLAGS) $(LDFLAGS) -o $@
$(AM_CXXFLAGS) $(CXXFLAGS) $(LDFLAGS) -lv3test -L. -o $@
noinst_LIBRARIES = libv3test.a
libv3test_a_SOURCES = \
testsuite_abi.cc \
testsuite_allocator.cc \
testsuite_hooks.cc
abi_check_SOURCES = abi_check.cc
abi_check_DEPENDENCIES = libv3test.a
# Generated lists of files to run. All of these names are valid make
# targets, if you wish to generate a list manually.
@ -282,9 +290,6 @@ lists_of_files = \
testsuite_files_interactive \
testsuite_files_performance
noinst_LIBRARIES = libv3test.a
libv3test_a_SOURCES = testsuite_hooks.cc testsuite_allocator.cc
abi_check_SOURCES = abi_check.cc
baseline_file = ${baseline_dir}/baseline_symbols.txt
extract_symvers = $(glibcxx_srcdir)/scripts/extract_symvers

View File

@ -1,311 +1,38 @@
// Utility for libstdc++ ABI analysis -*- C++ -*-
// -*- C++ -*-
// Copyright (C) 2002, 2003 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 2, or (at your option)
// any later version.
// Copyright (C) 2004 Free Software Foundation, Inc.
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License as
// published by the Free Software Foundation; either version 2, or (at
// your option) any later version.
// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING. If not, write to the Free
// Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
// USA.
// This library is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// General Public License for more details.
// As a special exception, you may use this file as part of a free software
// library without restriction. Specifically, if other files instantiate
// templates or use macros or inline functions from this file, or you compile
// this file and link it with other files to produce an executable, this
// file does not by itself cause the resulting executable to be covered by
// the GNU General Public License. This exception does not however
// invalidate any other reasons why the executable file might be covered by
// the GNU General Public License.
// You should have received a copy of the GNU General Public License
// along with this library; see the file COPYING. If not, write to
// the Free Software Foundation, 59 Temple Place - Suite 330, Boston,
// MA 02111-1307, USA.
// As a special exception, you may use this file as part of a free
// software library without restriction. Specifically, if other files
// instantiate templates or use macros or inline functions from this
// file, or you compile this file and link it with other files to
// produce an executable, this file does not by itself cause the
// resulting executable to be covered by the GNU General Public
// License. This exception does not however invalidate any other
// reasons why the executable file might be covered by the GNU General
// Public License.
// Benjamin Kosnik <bkoz@redhat.com>
// Blame subsequent hacks on Loren J. Rittle <ljrittle@acm.org>, Phil
// Edwards <pme@gcc.gnu.org>, and a cast of dozens at libstdc++@gcc.gnu.org.
#include <string>
#include <ext/hash_map>
#include <deque>
#include <sstream>
#include <fstream>
#include "testsuite_abi.h"
#include <iostream>
#include <cxxabi.h>
#include <stdlib.h> // for system(3)
#include <unistd.h> // for access(2)
struct symbol_info
{
enum category { none, function, object, error };
category type;
std::string name;
std::string demangled_name;
int size;
std::string version_name;
symbol_info() : type(none), size(0) { }
symbol_info(const symbol_info& other)
: type(other.type), name(other.name), demangled_name(other.demangled_name),
size(other.size), version_name(other.version_name) { }
};
namespace __gnu_cxx
{
using namespace std;
template<>
struct hash<string>
{
size_t operator()(const string& s) const
{
const collate<char>& c = use_facet<collate<char> >(locale::classic());
return c.hash(s.c_str(), s.c_str() + s.size());
}
};
}
typedef std::deque<std::string> symbol_names;
typedef __gnu_cxx::hash_map<std::string, symbol_info> symbol_infos;
bool
check_version(const symbol_info& test, bool added = false)
{
typedef std::vector<std::string> compat_list;
static compat_list known_versions;
if (known_versions.empty())
{
known_versions.push_back("GLIBCPP_3.2"); // base version
known_versions.push_back("GLIBCPP_3.2.1");
known_versions.push_back("GLIBCPP_3.2.2");
known_versions.push_back("GLIBCPP_3.2.3"); // gcc-3.3.0
known_versions.push_back("GLIBCXX_3.4");
known_versions.push_back("CXXABI_1.2");
known_versions.push_back("CXXABI_1.2.1");
known_versions.push_back("CXXABI_1.3");
}
compat_list::iterator begin = known_versions.begin();
compat_list::iterator end = known_versions.end();
// Check version names for compatibility...
compat_list::iterator it1 = find(begin, end, test.version_name);
// Check for weak label.
compat_list::iterator it2 = find(begin, end, test.name);
// Check that added symbols aren't added in the base version.
bool compat = true;
if (added && test.version_name == known_versions[0])
compat = false;
if (it1 == end && it2 == end)
compat = false;
return compat;
}
bool
check_compatible(const symbol_info& lhs, const symbol_info& rhs,
bool verbose = false)
{
using namespace std;
bool ret = true;
const char tab = '\t';
// Check to see if symbol_infos are compatible.
if (lhs.type != rhs.type)
{
ret = false;
if (verbose)
{
cout << tab << "incompatible types" << endl;
}
}
if (lhs.name != rhs.name)
{
ret = false;
if (verbose)
{
cout << tab << "incompatible names" << endl;
}
}
if (lhs.size != rhs.size)
{
ret = false;
if (verbose)
{
cout << tab << "incompatible sizes" << endl;
cout << tab << lhs.size << endl;
cout << tab << rhs.size << endl;
}
}
if (lhs.version_name != rhs.version_name
&& !check_version(lhs) && !check_version(rhs))
{
ret = false;
if (verbose)
{
cout << tab << "incompatible versions" << endl;
cout << tab << lhs.version_name << endl;
cout << tab << rhs.version_name << endl;
}
}
if (verbose)
cout << endl;
return ret;
}
const char*
demangle(const std::string& mangled)
{
const char* name;
if (mangled[0] != '_' || mangled[1] != 'Z')
{
// This is not a mangled symbol, thus has "C" linkage.
name = mangled.c_str();
}
else
{
// Use __cxa_demangle to demangle.
int status = 0;
name = abi::__cxa_demangle(mangled.c_str(), 0, 0, &status);
if (!name)
{
switch (status)
{
case 0:
name = "error code = 0: success";
break;
case -1:
name = "error code = -1: memory allocation failure";
break;
case -2:
name = "error code = -2: invalid mangled name";
break;
case -3:
name = "error code = -3: invalid arguments";
break;
default:
name = "error code unknown - who knows what happened";
}
}
}
return name;
}
void
line_to_symbol_info(std::string& input, symbol_info& output)
{
using namespace std;
const char delim = ':';
const char version_delim = '@';
const string::size_type npos = string::npos;
string::size_type n = 0;
// Set the type.
if (input.find("FUNC") == 0)
output.type = symbol_info::function;
else if (input.find("OBJECT") == 0)
output.type = symbol_info::object;
else
output.type = symbol_info::error;
n = input.find_first_of(delim);
if (n != npos)
input.erase(input.begin(), input.begin() + n + 1);
// Iff object, get size info.
if (output.type == symbol_info::object)
{
n = input.find_first_of(delim);
if (n != npos)
{
string size(input.begin(), input.begin() + n);
istringstream iss(size);
int x;
iss >> x;
if (!iss.fail())
output.size = x;
input.erase(input.begin(), input.begin() + n + 1);
}
}
// Set the name.
n = input.find_first_of(version_delim);
if (n != npos)
{
// Found version string.
output.name = string(input.begin(), input.begin() + n);
n = input.find_last_of(version_delim);
input.erase(input.begin(), input.begin() + n + 1);
// Set version name.
output.version_name = input;
}
else
{
// No versioning info.
output.name = string(input.begin(), input.end());
input.erase(input.begin(), input.end());
}
// Set the demangled name.
output.demangled_name = demangle(output.name);
}
void
create_symbol_data(const char* file, symbol_infos& symbols,
symbol_names& names)
{
// Parse list of symbols in file into vectors of symbol_info.
// For 3.2.0 on x86/linux, this usually is
// 947 non-weak symbols
// 2084 weak symbols
using namespace std;
ifstream ifs(file);
if (ifs.is_open())
{
// Organize input into container of symbol_info objects.
const string empty;
string line = empty;
while (getline(ifs, line).good())
{
symbol_info symbol;
line_to_symbol_info(line, symbol);
symbols[symbol.name] = symbol;
names.push_back(symbol.name);
line = empty;
}
}
}
void
report_symbol_info(const symbol_info& symbol, std::size_t n, bool ret = true)
{
using namespace std;
const char tab = '\t';
// Add any other information to display here.
cout << tab << symbol.demangled_name << endl;
cout << tab << symbol.name << endl;
cout << tab << symbol.version_name << endl;
if (ret)
cout << endl;
}
int
main(int argc, char** argv)
@ -313,144 +40,54 @@ main(int argc, char** argv)
using namespace std;
// Get arguments. (Heading towards getopt_long, I can feel it.)
bool verbose = false;
string argv1 = argc > 1 ? argv[1] : "";
if (argv1 == "--help" || argc < 4)
{
cerr << "usage: abi_check --check current baseline\n"
" --check-verbose current baseline\n"
" --help\n\n"
"Where CURRENT is a file containing the current results from\n"
"extract_symvers, and BASELINE is one from config/abi.\n"
" --examine symbol current\n"
" --help\n"
"\n"
"All arguments are string literals.\n"
"CURRENT is a file generated byextract_symvers.\n"
"BASELINE is a file from config/abi.\n"
"SYMBOL is a mangled name.\n"
<< endl;
exit(1);
}
else if (argv1 == "--check-verbose")
verbose = true;
// Quick sanity/setup check for arguments.
const char* test_file = argv[2];
const char* baseline_file = argv[3];
if (access(test_file, R_OK) != 0)
if (argv1.find("--check") != string::npos)
{
cerr << "Cannot read symbols file " << test_file
<< ", did you forget to build first?" << endl;
exit(1);
}
if (access(baseline_file, R_OK) != 0)
{
cerr << "Cannot read baseline file " << baseline_file << endl;
exit(1);
}
// Input both lists of symbols into container.
symbol_infos baseline_symbols;
symbol_names baseline_names;
symbol_infos test_symbols;
symbol_names test_names;
create_symbol_data(baseline_file, baseline_symbols, baseline_names);
create_symbol_data(test_file, test_symbols, test_names);
// Sanity check results.
const symbol_names::size_type baseline_size = baseline_names.size();
const symbol_names::size_type test_size = test_names.size();
if (!baseline_size || !test_size)
{
cerr << "Problems parsing the list of exported symbols." << endl;
exit(2);
}
// Sort out names.
// Assuming baseline_names, test_names are both unique w/ no duplicates.
//
// The names added to missing_names are baseline_names not found in
// test_names
// -> symbols that have been deleted.
//
// The names added to added_names are test_names are names not in
// baseline_names
// -> symbols that have been added.
symbol_names shared_names;
symbol_names missing_names;
symbol_names added_names = test_names;
for (size_t i = 0; i < baseline_size; ++i)
{
string what(baseline_names[i]);
symbol_names::iterator end = added_names.end();
symbol_names::iterator it = find(added_names.begin(), end, what);
if (it != end)
bool verbose = false;
if (argv1 == "--check-verbose")
verbose = true;
// Quick sanity/setup check for arguments.
const char* test_file = argv[2];
const char* baseline_file = argv[3];
if (access(test_file, R_OK) != 0)
{
// Found.
shared_names.push_back(what);
added_names.erase(it);
cerr << "Cannot read symbols file " << test_file
<< ", did you forget to build first?" << endl;
exit(1);
}
else
missing_names.push_back(what);
}
// Check missing names for compatibility.
typedef pair<symbol_info, symbol_info> symbol_pair;
vector<symbol_pair> incompatible;
for (size_t i = 0; i < missing_names.size(); ++i)
{
symbol_info base = baseline_symbols[missing_names[i]];
incompatible.push_back(symbol_pair(base, base));
}
// Check shared names for compatibility.
for (size_t i = 0; i < shared_names.size(); ++i)
{
symbol_info base = baseline_symbols[shared_names[i]];
symbol_info test = test_symbols[shared_names[i]];
if (!check_compatible(base, test))
incompatible.push_back(symbol_pair(base, test));
}
// Check added names for compatibility.
for (size_t i = 0; i < added_names.size(); ++i)
{
symbol_info test = test_symbols[added_names[i]];
if (!check_version(test, true))
incompatible.push_back(symbol_pair(test, test));
}
// Report results.
if (verbose && added_names.size())
{
cout << added_names.size() << " added symbols " << endl;
for (size_t j = 0; j < added_names.size() ; ++j)
report_symbol_info(test_symbols[added_names[j]], j + 1);
}
if (verbose && missing_names.size())
{
cout << missing_names.size() << " missing symbols " << endl;
for (size_t j = 0; j < missing_names.size() ; ++j)
report_symbol_info(baseline_symbols[missing_names[j]], j + 1);
}
if (verbose && incompatible.size())
{
cout << incompatible.size() << " incompatible symbols " << endl;
for (size_t j = 0; j < incompatible.size() ; ++j)
if (access(baseline_file, R_OK) != 0)
{
// First, report name.
const symbol_info& base = incompatible[j].first;
const symbol_info& test = incompatible[j].second;
report_symbol_info(test, j + 1, false);
// Second, report reason or reasons incompatible.
check_compatible(base, test, true);
cerr << "Cannot read baseline file " << baseline_file << endl;
exit(1);
}
compare_symbols(baseline_file, test_file, verbose);
}
cout << "\n\t\t=== libstdc++-v3 check-abi Summary ===" << endl;
cout << endl;
cout << "# of added symbols:\t\t " << added_names.size() << endl;
cout << "# of missing symbols:\t\t " << missing_names.size() << endl;
cout << "# of incompatible symbols:\t " << incompatible.size() << endl;
cout << endl;
cout << "using: " << baseline_file << endl;
if (argv1 == "--examine")
{
const char* file = argv[3];
if (access(file, R_OK) != 0)
{
cerr << "Cannot read symbol file " << file << endl;
exit(1);
}
examine_symbol(argv[2], file);
}
return 0;
}

View File

@ -0,0 +1,462 @@
// -*- C++ -*-
// Copyright (C) 2004 Free Software Foundation, Inc.
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License as
// published by the Free Software Foundation; either version 2, or (at
// your option) any later version.
// This library is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this library; see the file COPYING. If not, write to
// the Free Software Foundation, 59 Temple Place - Suite 330, Boston,
// MA 02111-1307, USA.
// As a special exception, you may use this file as part of a free
// software library without restriction. Specifically, if other files
// instantiate templates or use macros or inline functions from this
// file, or you compile this file and link it with other files to
// produce an executable, this file does not by itself cause the
// resulting executable to be covered by the GNU General Public
// License. This exception does not however invalidate any other
// reasons why the executable file might be covered by the GNU General
// Public License.
// Benjamin Kosnik <bkoz@redhat.com>
#include "testsuite_abi.h"
#include <sstream>
#include <fstream>
#include <iostream>
using namespace std;
void
symbol::init(string& data)
{
const char delim = ':';
const char version_delim = '@';
const string::size_type npos = string::npos;
string::size_type n = 0;
// Set the type.
if (data.find("FUNC") == 0)
type = symbol::function;
else if (data.find("OBJECT") == 0)
type = symbol::object;
else
type = symbol::error;
n = data.find_first_of(delim);
if (n != npos)
data.erase(data.begin(), data.begin() + n + 1);
// Iff object, get size info.
if (type == symbol::object)
{
n = data.find_first_of(delim);
if (n != npos)
{
string size(data.begin(), data.begin() + n);
istringstream iss(size);
int x;
iss >> x;
if (!iss.fail())
size = x;
data.erase(data.begin(), data.begin() + n + 1);
}
}
// Set the name.
n = data.find_first_of(version_delim);
if (n != npos)
{
// Found version string.
name = string(data.begin(), data.begin() + n);
n = data.find_last_of(version_delim);
data.erase(data.begin(), data.begin() + n + 1);
// Set version name.
version_name = data;
}
else
{
// No versioning info.
name = string(data.begin(), data.end());
data.erase(data.begin(), data.end());
}
// Set the demangled name.
demangled_name = demangle(name);
}
void
symbol::print() const
{
const char tab = '\t';
cout << tab << name << endl;
cout << tab << demangled_name << endl;
cout << tab << version_name << endl;
string type_string;
switch (type)
{
case none:
type_string = "none";
break;
case function:
type_string = "function";
break;
case object:
type_string = "object";
break;
case error:
type_string = "error";
break;
default:
type_string = "<default>";
}
cout << tab << type_string << endl;
if (type == object)
cout << tab << size << endl;
string status_string;
switch (status)
{
case unknown:
status_string = "unknown";
break;
case added:
status_string = "added";
break;
case subtracted:
status_string = "subtracted";
break;
case compatible:
status_string = "compatible";
break;
case incompatible:
status_string = "incompatible";
break;
default:
status_string = "<default>";
}
cout << tab << status_string << endl;
}
bool
check_version(const symbol& test, bool added)
{
typedef std::vector<std::string> compat_list;
static compat_list known_versions;
if (known_versions.empty())
{
known_versions.push_back("GLIBCPP_3.2"); // base version
known_versions.push_back("GLIBCPP_3.2.1");
known_versions.push_back("GLIBCPP_3.2.2");
known_versions.push_back("GLIBCPP_3.2.3"); // gcc-3.3.0
known_versions.push_back("GLIBCXX_3.4");
known_versions.push_back("CXXABI_1.2");
known_versions.push_back("CXXABI_1.2.1");
known_versions.push_back("CXXABI_1.3");
}
compat_list::iterator begin = known_versions.begin();
compat_list::iterator end = known_versions.end();
// Check version names for compatibility...
compat_list::iterator it1 = find(begin, end, test.version_name);
// Check for weak label.
compat_list::iterator it2 = find(begin, end, test.name);
// Check that added symbols aren't added in the base version.
bool compat = true;
if (added && test.version_name == known_versions[0])
compat = false;
if (it1 == end && it2 == end)
compat = false;
return compat;
}
bool
check_compatible(const symbol& lhs, const symbol& rhs, bool verbose)
{
bool ret = true;
const char tab = '\t';
// Check to see if symbol_objects are compatible.
if (lhs.type != rhs.type)
{
ret = false;
if (verbose)
cout << tab << "incompatible types" << endl;
}
if (lhs.name != rhs.name)
{
ret = false;
if (verbose)
cout << tab << "incompatible names" << endl;
}
if (lhs.size != rhs.size)
{
ret = false;
if (verbose)
{
cout << tab << "incompatible sizes" << endl;
cout << tab << lhs.size << endl;
cout << tab << rhs.size << endl;
}
}
if (lhs.version_name != rhs.version_name
&& !check_version(lhs) && !check_version(rhs))
{
ret = false;
if (verbose)
{
cout << tab << "incompatible versions" << endl;
cout << tab << lhs.version_name << endl;
cout << tab << rhs.version_name << endl;
}
}
if (verbose)
cout << endl;
return ret;
}
bool
has_symbol(const string& mangled, const symbols& s) throw()
{
const symbol_names& names = s.first;
symbol_names::const_iterator i = find(names.begin(), names.end(), mangled);
return i != names.end();
}
symbol&
get_symbol(const string& mangled, const symbols& s)
{
const symbol_names& names = s.first;
symbol_names::const_iterator i = find(names.begin(), names.end(), mangled);
if (i != names.end())
{
symbol_objects objects = s.second;
return objects[mangled];
}
else
{
ostringstream os;
os << "get_symbol failed for symbol " << mangled;
throw symbol_error(os.str());
}
}
void
examine_symbol(const char* name, const char* file)
{
try
{
symbols s = create_symbols(file);
symbol& sym = get_symbol(name, s);
sym.print();
}
catch(...)
{ throw; }
}
void
compare_symbols(const char* baseline_file, const char* test_file,
bool verbose)
{
// Input both lists of symbols into container.
symbols baseline = create_symbols(baseline_file);
symbols test = create_symbols(test_file);
symbol_names& baseline_names = baseline.first;
symbol_objects& baseline_objects = baseline.second;
symbol_names& test_names = test.first;
symbol_objects& test_objects = test.second;
// Sanity check results.
const symbol_names::size_type baseline_size = baseline_names.size();
const symbol_names::size_type test_size = test_names.size();
if (!baseline_size || !test_size)
{
cerr << "Problems parsing the list of exported symbols." << endl;
exit(2);
}
// Sort out names.
// Assuming baseline_names, test_names are both unique w/ no duplicates.
//
// The names added to missing_names are baseline_names not found in
// test_names
// -> symbols that have been deleted.
//
// The names added to added_names are test_names are names not in
// baseline_names
// -> symbols that have been added.
symbol_names shared_names;
symbol_names missing_names;
symbol_names added_names = test_names;
for (size_t i = 0; i < baseline_size; ++i)
{
string what(baseline_names[i]);
symbol_names::iterator end = added_names.end();
symbol_names::iterator it = find(added_names.begin(), end, what);
if (it != end)
{
// Found.
shared_names.push_back(what);
added_names.erase(it);
}
else
missing_names.push_back(what);
}
// Check missing names for compatibility.
typedef pair<symbol, symbol> symbol_pair;
vector<symbol_pair> incompatible;
for (size_t i = 0; i < missing_names.size(); ++i)
{
symbol base = baseline_objects[missing_names[i]];
incompatible.push_back(symbol_pair(base, base));
}
// Check shared names for compatibility.
for (size_t i = 0; i < shared_names.size(); ++i)
{
symbol base = baseline_objects[shared_names[i]];
symbol test = test_objects[shared_names[i]];
if (!check_compatible(base, test))
incompatible.push_back(symbol_pair(base, test));
}
// Check added names for compatibility.
for (size_t i = 0; i < added_names.size(); ++i)
{
symbol test = test_objects[added_names[i]];
if (!check_version(test, true))
incompatible.push_back(symbol_pair(test, test));
}
// Report results.
if (verbose && added_names.size())
{
cout << added_names.size() << " added symbols " << endl;
for (size_t j = 0; j < added_names.size() ; ++j)
test_objects[added_names[j]].print();
}
if (verbose && missing_names.size())
{
cout << missing_names.size() << " missing symbols " << endl;
for (size_t j = 0; j < missing_names.size() ; ++j)
baseline_objects[missing_names[j]].print();
}
if (verbose && incompatible.size())
{
cout << incompatible.size() << " incompatible symbols " << endl;
for (size_t j = 0; j < incompatible.size() ; ++j)
{
// First, report name.
const symbol& base = incompatible[j].first;
const symbol& test = incompatible[j].second;
test.print();
// Second, report reason or reasons incompatible.
check_compatible(base, test, true);
}
}
cout << "\n\t\t=== libstdc++-v3 check-abi Summary ===" << endl;
cout << endl;
cout << "# of added symbols:\t\t " << added_names.size() << endl;
cout << "# of missing symbols:\t\t " << missing_names.size() << endl;
cout << "# of incompatible symbols:\t " << incompatible.size() << endl;
cout << endl;
cout << "using: " << baseline_file << endl;
}
symbols
create_symbols(const char* file)
{
symbols s;
ifstream ifs(file);
if (ifs.is_open())
{
// Organize file data into container of symbol objects.
symbol_names& names = s.first;
symbol_objects& objects = s.second;
const string empty;
string line = empty;
while (getline(ifs, line).good())
{
symbol tmp;
tmp.init(line);
objects[tmp.name] = tmp;
names.push_back(tmp.name);
line = empty;
}
}
else
{
ostringstream os;
os << "create_symbols failed for file " << file;
throw runtime_error(os.str());
}
return s;
}
const char*
demangle(const std::string& mangled)
{
const char* name;
if (mangled[0] != '_' || mangled[1] != 'Z')
{
// This is not a mangled symbol, thus has "C" linkage.
name = mangled.c_str();
}
else
{
// Use __cxa_demangle to demangle.
int status = 0;
name = abi::__cxa_demangle(mangled.c_str(), 0, 0, &status);
if (!name)
{
switch (status)
{
case 0:
name = "error code = 0: success";
break;
case -1:
name = "error code = -1: memory allocation failure";
break;
case -2:
name = "error code = -2: invalid mangled name";
break;
case -3:
name = "error code = -3: invalid arguments";
break;
default:
name = "error code unknown - who knows what happened";
}
}
}
return name;
}

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@ -0,0 +1,129 @@
// -*- C++ -*-
// Copyright (C) 2004 Free Software Foundation, Inc.
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License as
// published by the Free Software Foundation; either version 2, or (at
// your option) any later version.
// This library is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this library; see the file COPYING. If not, write to
// the Free Software Foundation, 59 Temple Place - Suite 330, Boston,
// MA 02111-1307, USA.
// As a special exception, you may use this file as part of a free
// software library without restriction. Specifically, if other files
// instantiate templates or use macros or inline functions from this
// file, or you compile this file and link it with other files to
// produce an executable, this file does not by itself cause the
// resulting executable to be covered by the GNU General Public
// License. This exception does not however invalidate any other
// reasons why the executable file might be covered by the GNU General
// Public License.
// Benjamin Kosnik <bkoz@redhat.com>
#include <string>
#include <stdexcept>
#include <deque>
#include <ext/hash_map>
#include <cxxabi.h>
// Encapsulates symbol characteristics.
struct symbol
{
enum category { none, function, object, error };
enum designation { unknown, added, subtracted, compatible, incompatible };
enum compatibility
{
compat_type = 1,
compat_name = 2,
compat_size = 4,
compat_version = 8
};
category type;
std::string name;
std::string demangled_name;
int size;
std::string version_name;
designation status;
symbol() : type(none), size(0), status(unknown) { }
symbol(const symbol& other)
: type(other.type), name(other.name), demangled_name(other.demangled_name),
size(other.size), version_name(other.version_name),
status(other.status) { }
void
print() const;
void
init(std::string& data);
};
struct symbol_error : public std::logic_error
{
explicit symbol_error(const std::string& s) : std::logic_error(s) { }
};
typedef __gnu_cxx::hash_map<std::string, symbol> symbol_objects;
typedef std::deque<std::string> symbol_names;
typedef std::pair<symbol_names, symbol_objects> symbols;
// Check.
bool
check_version(const symbol& test, bool added = false);
bool
check_compatible(const symbol& lhs, const symbol& rhs, bool verbose = false);
// Examine.
bool
has_symbol(const std::string& mangled, const symbols& list) throw();
symbol&
get_symbol(const std::string& mangled, const symbols& list);
extern "C" void
examine_symbol(const char* name, const char* file);
extern "C" void
compare_symbols(const char* baseline_file, const char* test_file, bool verb);
// Util.
symbols
create_symbols(const char* file);
const char*
demangle(const std::string& mangled);
// Specialization.
namespace __gnu_cxx
{
using namespace std;
template<>
struct hash<string>
{
size_t operator()(const string& s) const
{
const collate<char>& c = use_facet<collate<char> >(locale::classic());
return c.hash(s.c_str(), s.c_str() + s.size());
}
};
}