Simon pointed out that gdb would not build with clang, due to the
addition of -Wimplicit-fallthrough. This patch fixes the problem by
using -Wimplicit-fallthrough=3 -- this does not work with clang,
bypassing the issue.
Tested by rebuilding with both gcc and clang; and also by verifying
that -Wimplicit-fallthrough=3 is used in the gcc build.
I will file a follow-up bug to convert the fall-through comments to a
form that can be used by both clang and gcc.
gdb/ChangeLog
2018-05-10 Tom Tromey <tom@tromey.com>
* configure: Rebuild.
* warning.m4 (AM_GDB_WARNINGS): Use -Wimplicit-fallthrough=3.
gdb/gdbserver/ChangeLog
2018-05-10 Tom Tromey <tom@tromey.com>
* configure: Rebuild.
This adds -Wduplicated-cond to warnings.m4. This caught one bug.
I tried adding -Wduplicated-branches as well, but it results in some
spurious failures from code like this in cgen.h:
#define CGEN_ATTR_TYPE(n) \
struct { unsigned int bool_; \
CGEN_ATTR_VALUE_TYPE nonbool[(n) ? (n) : 1]; }
This will trigger a warning if passed n==1, which seems like a
perfectly valid thing to do; and there were other issues like this as
well.
ChangeLog
2018-05-07 Tom Tromey <tom@tromey.com>
* configure: Rebuild.
* warning.m4 (AM_GDB_WARNINGS): Add -Wduplicated-cond.
gdbserver/ChangeLog
2018-05-07 Tom Tromey <tom@tromey.com>
* configure: Rebuild.
This adds -Wimplicit-fallthrough to the set of default warnings.
2018-05-04 Tom Tromey <tom@tromey.com>
* configure: Rebuild.
* warning.m4 (AM_GDB_WARNINGS): Add -Wimplicit-fallthrough.
gdbserver/ChangeLog
2018-05-04 Tom Tromey <tom@tromey.com>
* configure: Rebuild.
I noticed the existence of -Wsuggest-override and so this patch
enables it for gdb. It found a few spots that could use "override".
Also I went ahead and removed all uses of the "OVERRIDE" macro.
Using override is beneficial because it makes it harder to change a
base class and then forget to change a derived class.
Tested by the buildbot.
ChangeLog
2018-04-27 Tom Tromey <tom@tromey.com>
* configure: Rebuild.
* warning.m4 (AM_GDB_WARNINGS): Add -Wsuggest-override.
* dwarf2loc.c (class dwarf_evaluate_loc_desc): Use "override", not
"OVERRIDE".
(class symbol_needs_eval_context): Likewise.
* dwarf2read.c (mock_mapped_index::symbol_name_count)
(mock_mapped_index::symbol_name_at): Use "override". Remove
"virtual".
* dwarf2-frame.c (dwarf_expr_executor::get_addr_index): Use
"override".
(class dwarf_expr_executor): Use "override", not "OVERRIDE".
* aarch64-tdep.c (instruction_reader::read): Use "override".
(instruction_reader_test::read): Likewise.
* arm-tdep.c (instruction_reader::read): Use "override".
(instruction_reader_thumb::read): Likewise.
gdbserver/ChangeLog
2018-04-27 Tom Tromey <tom@tromey.com>
* configure: Rebuild.
As shown in PR 23022, building with clang-6 and Python 2 trips on the
fact that the Python 2 headers use the "register" keyword:
/usr/include/python2.7/unicodeobject.h:534:5: error: 'register' storage class specifier is deprecated and incompatible with C++17 [-Werror,-Wdeprecated-register]
register PyObject *obj, /* Object */
^~~~~~~~~
This patch adds -Wno-error=deprecated-register to our flags, so that we can
still see this class of warnings, but they don't cause a build failure.
gdb/ChangeLog:
PR gdb/23022
* warning.m4: Add -Wno-error=deprecated-register.
* configure: Re-generate.
I just tried to compile gdb trunk on Solaris 11.4 (formerly 12), and
failed for a couple of reasons:
*
In file included from /usr/include/python2.7/Python.h:128:0,
from /vol/src/gnu/gdb/gdb/dist/gdb/python/python-internal.h:94,
from /vol/src/gnu/gdb/gdb/dist/gdb/python/py-instruction.h:23,
from /vol/src/gnu/gdb/gdb/dist/gdb/python/py-instruction.c:21:
/usr/include/python2.7/ceval.h:67:0: error: ignoring #pragma no_inline [-Werror=unknown-pragmas]
#pragma no_inline(PyEval_EvalFrameEx)
^
New in Solaris 11.4: <python2.7/ceval.h> uses a Studio-only #pragma.
I've disabled the warning in warnings.m4.
*
/vol/src/gnu/gdb/gdb/dist/gdb/ser-pipe.c: In function ‘int pipe_open(serial*, const char*)’:
/vol/src/gnu/gdb/gdb/dist/gdb/ser-pipe.c:77:9: error: ‘pid_t vfork()’ is deprecated (declared at /usr/include/unistd.h:659) [-Werror=deprecated-declarations]
pid = vfork ();
^
/vol/src/gnu/gdb/gdb/dist/gdb/ser-pipe.c:77:16: error: ‘pid_t vfork()’ is deprecated (declared at /usr/include/unistd.h:659) [-Werror=deprecated-declarations]
pid = vfork ();
^
Since Solaris 11, vfork () is marked deprecated in <unistd.h>.
cf. vfork(2):
The vfork() and vforkx() functions are deprecated. Their sole legiti-
mate use as a prelude to an immediate call to a function from the exec
family can be achieved safely by posix_spawn(3C) or posix_spawnp(3C).
Again, I've disabled the warning.
*
/vol/src/gnu/gdb/gdb/dist/gdb/cli/cli-cmds.c: In function ‘void shell_escape(const char*, int)’:
/vol/src/gnu/gdb/gdb/dist/gdb/cli/cli-cmds.c:750:14: error: ‘pid_t vfork()’ is deprecated (declared at /usr/include/unistd.h:659) [-Werror=deprecated-declarations]
if ((pid = vfork ()) == 0)
^
/vol/src/gnu/gdb/gdb/dist/gdb/cli/cli-cmds.c:750:21: error: ‘pid_t vfork()’ is deprecated (declared at /usr/include/unistd.h:659) [-Werror=deprecated-declarations]
if ((pid = vfork ()) == 0)
^
Same problem.
*
/vol/src/gnu/gdb/gdb/dist/gdb/procfs.c: In function ‘void procfs_init_inferior(target_ops*, int)’:
/vol/src/gnu/gdb/gdb/dist/gdb/procfs.c:4380:30: error: ‘START_INFERIOR_TRAPS_EXPECTED’ was not declared in this scope
gdb_startup_inferior (pid, START_INFERIOR_TRAPS_EXPECTED);
^
defined in nat/fork-inferior.h, need to include that header
/vol/src/gnu/gdb/gdb/dist/gdb/procfs.c: In function ‘void procfs_create_inferior(target_ops*, const char*, const string&, char**, int)’:
/vol/src/gnu/gdb/gdb/dist/gdb/procfs.c:4605:38: error: ‘fork_inferior’ was not declared in this scope
NULL, NULL, shell_file, NULL);
^
likewise
/vol/src/gnu/gdb/gdb/dist/gdb/procfs.c: In function ‘void procfs_info_proc(target_ops*, const char*, info_proc_what)’:
/vol/src/gnu/gdb/gdb/dist/gdb/procfs.c:5124:20: error: ‘argv’ was not declared in this scope
for (char *arg : argv)
^
Typo, should be built_argv instead!
*
Undefined first referenced
symbol in file
fork_inferior(char const*, std::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, char**, void (*)(), void (*)(int), void (*)(), char const*, void (*)(char const*, char* const*, char* const*)) procfs.o
startup_inferior(int, int, target_waitstatus*, ptid_t*) fork-child.o
ld: fatal: symbol referencing errors
collect2: error: ld returned 1 exit status
make[2]: *** [Makefile:2249: gdb] Error 1
Need to add fork-inferior.o to NATDEPFILES.
With the changes below, I can build gdb on sparcv9-sun-solaris2.11 and
amd64-pc-solaris2.11 and a simple smoke test (gdb/gdb gdb/gdb) works.
clang complains that for some types, we use both the class and struct
keywords in different places. It's not really a problem, so I think we
can safely turn this warning off.
gdb/ChangeLog:
* configure: Re-generate.
* warning.m4 (build_warnings): Add -Wno-mismatched-tags.
gdb/gdbserver/ChangeLog:
* configure: Re-generate.
In warning.m4, we pass all the warning flags one by one to the compiler
to test if they are supported by this particular compiler. If the
compiler exits with an error, we conclude that this warning flag is not
supported and exclude it. This allows us to use warning flags without
having to worry about which versions of which compilers support each
flag.
clang, by default, only emits a warning if an unknown flag is passed:
warning: unknown warning option '-Wfoo' [-Wunknown-warning-option]
The result is that we think that all the warning flags we use are
supported by clang (they are not), and the compilation fails later when
building with -Werror, since the aforementioned warning becomes an
error. The fix is to also pass -Werror when probing for supported
flags, then we'll correctly get an error when using an unknown warning,
and we'll exclude it:
error: unknown warning option '-Wfoo' [-Werror,-Wunknown-warning-option]
I am not sure why there is a change in a random comment in
gdbserver/configure, but I suppose it's a leftfover from a previous
patch, so I included it.
gdb/ChangeLog:
* configure: Re-generate.
* warning.m4: Pass -Werror to compiler when checking for
supported warning flags.
gdb/gdbserver/ChangeLog:
* configure: Re-generate.
Newer GCCs are triggering false-positive -Wmaybe-uninitialized
warnings around code that uses gdb::optional:
https://sourceware.org/ml/gdb-patches/2017-05/msg00118.html
Using std::optional wouldn't help, it triggers the same warnings:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80635
Initializing the variables to quiet the warning would defeat the
purpose of gdb::optional. Making the optional ctor memset its storage
would be a pessimization. Wrapping gdb::optional's internals with
"#pragma GCC diagnostic push/ignored/pop" doesn't work, we'd have to
wrap uses of gdb::optional instead, which I think would get unwieldy
and ugly as we start using gdb::optional more and more.
The -Wmaybe-uninitialized warning is documented as producing false
positives (unlike -Wuninialized), so until we find a better
workaround, disable -Werror for this warning. You'll still see the
warning when building gdb, but it won't cause a build failure.
Tested by building with gcc 4.8.5, 5.3.1, and gcc trunk (20170428).
gdb/ChangeLog:
2017-05-05 Pedro Alves <palves@redhat.com>
* warning.m4 (build_warnings): Add -Wno-error=maybe-uninitialized.
* configure: Regenerate.
gdb/gdbserver/ChangeLog:
2017-05-05 Pedro Alves <palves@redhat.com>
* configure: Regenerate.
AFAIK GDB is now free from -Wwrite-strings warnings. A few warnings may
be left behind in some host-specific code, but those should be few and
easy to fix.
gdb/ChangeLog:
2017-04-05 Pedro Alves <palves@redhat.com>
* warning.m4 (build_warnings): Remove -Wno-write-strings.
* configure: Regenerate.
gdb/gdbserver/ChangeLog:
2017-04-05 Pedro Alves <palves@redhat.com>
* configure: Regenerate.
This applies the second part of GDB's End of Year Procedure, which
updates the copyright year range in all of GDB's files.
gdb/ChangeLog:
Update copyright year range in all GDB files.
This removes all support for building gdb & gdbserver with a C
compiler from gdb & gdbserver's build machinery.
gdb/ChangeLog:
2016-09-05 Pedro Alves <palves@redhat.com>
* NEWS: Mention that a C++ compiler is now required.
* Makefile.in (COMPILER, COMPILER_CFLAGS): Remove.
(COMPILE.pre, CC_LD): Use CXX directly.
(INTERNAL_CFLAGS_BASE): Use CXXFLAGS directly.
* acinclude.m4: Don't include build-with-cxx.m4.
* build-with-cxx.m4: Delete file.
* configure.ac: Remove GDB_AC_BUILD_WITH_CXX call.
* warning.m4: Assume $enable_build_with_cxx is yes.
* configure: Regenerate.
gdb/gdbserver/ChangeLog:
2016-09-05 Pedro Alves <palves@redhat.com>
* Makefile.in (COMPILER, COMPILER_CFLAGS): Remove.
(COMPILE.pre, CC_LD): Use CXX directly.
(INTERNAL_CFLAGS_BASE): Use CXXFLAGS directly.
* acinclude.m4: Don't include build-with-cxx.m4.
* configure.ac: Remove GDB_AC_BUILD_WITH_CXX call.
* configure: Regenerate.