Binutils with MCST patches
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Andrew Burgess a8e9d24718 gdb: Show type summary for anonymous structures from c_print_typedef
Currently each language has a la_print_typedef method, this is only
used for the "info types" command.

The documentation for "info types" says:

   Print a brief description of all types whose names match the regular
   expression @var{regexp} (or all types in your program, if you supply
   no argument).

However, if we consider this C code:

   typedef struct {
     int a;
   } my_type;

Then currently with "info types" this will be printed like this:

   3:      typedef struct {
       int a;
   } my_type;

I see two problems with this, first the indentation is clearly broken,
second, if the struct contained more fields then it feels like the
actual type names could easily get lost in the noise.

Given that "info types" is about discovering type names, I think there
is an argument to be made that we should focus on giving _only_ the
briefest summary for "info types", and if the user wants to know more
they can take the type name and plug it into "ptype".  As such, I
propose that a better output would be:

   3:      typedef struct {...} my_type;

The user understands that there is a type called `my_type`, and that
it's an alias for an anonymous structure type.

The change to achieve this turns out to be pretty simple, but only
effects languages that make use of c_print_typedef, which are C, C++,
asm, minimal, d, go, objc, and opencl.  Other languages will for now
do whatever they used to do.

The patch to change how anonymous structs are displayed also changes
the display of anonymous enums, consider this code sample:

   typedef enum {
     AA, BB, CC
   } anon_enum_t;

This used to be displayed like this:

   3:      typedef enum {AA, BB, CC} anon_enum_t;

Which will quickly become cluttered for enums with a large number of
values.  The modified output looks like this:

   3:      typedef enum {...} anon_enum_t;

Again, the user can always make use of ptype if they want to see the
details of the anon_enum_t type.

It is worth pointing out that this change (to use {...}) only effects
anonymous structs and enums, named types don't change with this patch,
consider this code:

   struct struct_t {
     int i;
   };
   enum enum_t {
    AA, BB, CC
   };

The output from 'info types' remains unchanged, like this:

   4:      enum enum_t;
   1:      struct struct_t;

An additional area of interest is how C++ handles anonymous types used
within a typedef; enums are handled basically inline with how C
handles them, but structs (and classes) are slightly different.  The
behaviour before the patch is different, and is unchanged by this
patch.  Consider this code compiled for C++:

   typedef struct {
     int i;
   } struct_t;

Both before and after this patch, this is show by 'info types' as:

   3:      typedef struct_t struct_t;

Unions are displayed similarly to structs in both C and C++, the
handling of anonymous unions changes for C in the same way that
it changes for anonymous structs.

I did look at ada, as this is the only language to actually have some
tests for "info types", however, as I understand it ada doesn't really
support typedefs, however, by forcing the language we can see what ada
would print.  So, if we 'set language ada', then originally we printed
this:

   3:      record
       a: int;
   end record

Again the indentation is clearly broken, but we also have no mention
of the type name at all, which is odd, but understandable given the
lack of typedefs.  If I make a similar change as I'm proposing for C,
then we now get this output:

   3:      record ... end record

Which is even less informative I think.  However, the original output
_is_ tested for in gdb.ada/info_auto_lang.exp, and its not clear to me
if the change is a good one or not, so for now I have left this out.

gdb/ChangeLog:

	* c-typeprint.c (c_print_typedef): Pass -1 instead of 0 to
	type_print.

gdb/testsuite/ChangeLog:

	* gdb.ada/info_auto_lang.exp: Update expected results.
	* gdb.base/info-types.c: Add additional types to check.
	* gdb.base/info-types.exp: Update expected results.
2019-07-22 10:43:03 +01:00
bfd Automatic date update in version.in 2019-07-22 00:00:29 +00:00
binutils Prevent attempts to allocate excessive amounts of memory when parsing corrupt ELF files. 2019-06-28 15:30:43 +01:00
config Add markers for 2.32 branch to NEWS and ChangeLog files. 2019-01-19 15:55:50 +00:00
contrib Update dg-extract-results.* from gcc 2018-08-06 16:05:16 +02:00
cpu cpu,opcodes,gas: use %r0 and %r6 instead of %a and %ctf in eBPF disassembler 2019-07-19 15:35:43 +02:00
elfcpp [GOLD] PowerPC relocations for prefix insns 2019-07-13 09:57:50 +09:30
etc Update year range in copyright notice of binutils files 2019-01-01 22:06:53 +10:30
gas x86: Pass -O0 to assembler in noextreg.d 2019-07-19 11:07:59 -07:00
gdb gdb: Show type summary for anonymous structures from c_print_typedef 2019-07-22 10:43:03 +01:00
gnulib Fix gnulib/update-gnulib.sh 2019-06-21 13:23:59 +01:00
gold [GOLD] PowerPC R_PPC64_PCREL_OPT support 2019-07-13 09:57:50 +09:30
gprof Correct the alpha sorting of the short options in the usage description of the gprof program. 2019-05-20 17:17:24 +01:00
include [PowerPC64] pc-relative TLS relocations 2019-07-19 18:01:25 +09:30
intl Change version to 2.32.51 and regenerate configure and pot files. 2019-01-19 16:51:42 +00:00
ld PR24827, Linker loops forever if unterminated multi-line comment in script 2019-07-20 10:55:16 +09:30
libctf libctf: introduce ctf_func_type_{info,args}, ctf_type_aname_raw 2019-07-18 20:53:57 +01:00
libdecnumber Merge config/ changes from GCC. 2018-10-31 17:16:41 +00:00
libiberty Pull in patch for libiberty that fixes a stack exhaustion bug when demangling a pathalogically constructed mangled name. 2019-04-10 15:49:36 +01:00
opcodes cpu,opcodes,gas: use %r0 and %r6 instead of %a and %ctf in eBPF disassembler 2019-07-19 15:35:43 +02:00
readline [readline] Fix heap-buffer-overflow in update_line 2019-07-12 09:53:02 +02:00
sim sim/testsuite/or1k: Add tests for unordered compares 2019-06-13 21:27:10 +09:00
texinfo
zlib Merge config/ changes from GCC. 2018-10-31 17:16:41 +00:00
.cvsignore
.gitattributes Add a .gitattributes file for use with git-merge-changelog 2014-07-25 18:07:23 -04:00
.gitignore Add archives and make stamps to the .gitignore file. 2016-09-27 15:10:42 +01:00
ar-lib Bump to autoconf 2.69 and automake 1.15.1 2018-06-19 16:55:06 -04:00
ChangeLog adjust src-release following the renaming of gdb/common/ to gdb/gdbsupport/ 2019-07-13 18:00:32 -07:00
compile Update from upstream Automake 2014-11-16 13:43:48 +01:00
config-ml.in Update top level configure files by synchronizing them with gcc. 2018-01-10 15:29:21 +00:00
config.guess config.guess,config.sub: synchronize with config project master sources 2019-05-23 18:19:56 +02:00
config.rpath
config.sub config.guess,config.sub: synchronize with config project master sources 2019-05-23 18:19:56 +02:00
configure Move gnulib to top level 2019-06-14 12:40:02 -06:00
configure.ac Move gnulib to top level 2019-06-14 12:40:02 -06:00
COPYING
COPYING3
COPYING3.LIB
COPYING.LIB
COPYING.LIBGLOSS Update the address of the FSF in the copyright notice of files which were using the old address. 2017-12-14 12:48:55 +00:00
COPYING.NEWLIB
depcomp Update from upstream Automake 2014-11-16 13:43:48 +01:00
djunpack.bat
install-sh Update from upstream Automake 2014-11-16 13:43:48 +01:00
libtool.m4 Bump to autoconf 2.69 and automake 1.15.1 2018-06-19 16:55:06 -04:00
lt~obsolete.m4
ltgcc.m4
ltmain.sh
ltoptions.m4
ltsugar.m4
ltversion.m4
MAINTAINERS Move gnulib to top level 2019-06-14 12:40:02 -06:00
Makefile.def Move gnulib to top level 2019-06-14 12:40:02 -06:00
Makefile.in Move gnulib to top level 2019-06-14 12:40:02 -06:00
Makefile.tpl Revert "Sync top level files with versions from gcc." 2019-05-30 11:17:19 +01:00
makefile.vms
missing Update from upstream Automake 2014-11-16 13:43:48 +01:00
mkdep
mkinstalldirs Update from upstream Automake 2014-11-16 13:43:48 +01:00
move-if-change Update `move-if-change' from gnulib 2014-11-16 17:04:02 +01:00
multilib.am Merge autoconf / automake update changes from GCC. 2018-10-31 17:10:56 +00:00
README
README-maintainer-mode Bump to autoconf 2.69 and automake 1.15.1 2018-06-19 16:55:06 -04:00
setup.com
src-release.sh adjust src-release following the renaming of gdb/common/ to gdb/gdbsupport/ 2019-07-13 18:00:32 -07:00
symlink-tree
test-driver Bump to autoconf 2.69 and automake 1.15.1 2018-06-19 16:55:06 -04:00
ylwrap Update from upstream Automake 2014-11-16 13:43:48 +01:00

		   README for GNU development tools

This directory contains various GNU compilers, assemblers, linkers, 
debuggers, etc., plus their support routines, definitions, and documentation.

If you are receiving this as part of a GDB release, see the file gdb/README.
If with a binutils release, see binutils/README;  if with a libg++ release,
see libg++/README, etc.  That'll give you info about this
package -- supported targets, how to use it, how to report bugs, etc.

It is now possible to automatically configure and build a variety of
tools with one command.  To build all of the tools contained herein,
run the ``configure'' script here, e.g.:

	./configure 
	make

To install them (by default in /usr/local/bin, /usr/local/lib, etc),
then do:
	make install

(If the configure script can't determine your type of computer, give it
the name as an argument, for instance ``./configure sun4''.  You can
use the script ``config.sub'' to test whether a name is recognized; if
it is, config.sub translates it to a triplet specifying CPU, vendor,
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If you have more than one compiler on your system, it is often best to
explicitly set CC in the environment before running configure, and to
also set CC when running make.  For example (assuming sh/bash/ksh):

	CC=gcc ./configure
	make

A similar example using csh:

	setenv CC gcc
	./configure
	make

Much of the code and documentation enclosed is copyright by
the Free Software Foundation, Inc.  See the file COPYING or
COPYING.LIB in the various directories, for a description of the
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REPORTING BUGS: Again, see gdb/README, binutils/README, etc., for info
on where and how to report problems.