Stop using AC_HEADER_STDC since it is no longer supported in autoconf
2.72+. We require a C++ compiler that supports c++17, it's probably
safe to assume that the C compiler fully supports C89.
Approved-By: Simon Marchi <simon.marchi@efficios.com>
Add a few -Wunused-* diagnostic flags that look useful. Some are known
to gcc, some to clang, some to both. Fix the fallouts.
-Wunused-const-variable=1 is understood by gcc, but not clang.
-Wunused-const-variable would be undertsood by both, but for gcc at
least it would flag the unused const variables in headers. This doesn't
make sense to me, because as soon as one source file includes a header
but doesn't use a const variable defined in that header, it's an error.
With `=1`, gcc only warns about unused const variable in the main source
file. It's not a big deal that clang doesn't understand it though: any
instance of that problem will be flagged by any gcc build.
Change-Id: Ie20d99524b3054693f1ac5b53115bb46c89a5156
Approved-By: Tom Tromey <tom@tromey.com>
The mingw-w64 build breaks currently:
...
In file included from gdb/cli/cli-cmds.c:58:
gdbsupport/eintr.h: In function ‘pid_t gdb::waitpid(pid_t, int*, int)’:
gdbsupport/eintr.h:77:35: error: ‘::waitpid’ has not been declared; \
did you mean ‘gdb::waitpid’?
77 | return gdb::handle_eintr (-1, ::waitpid, pid, wstatus, options);
| ^~~~~~~
| gdb::waitpid
gdbsupport/eintr.h:75:1: note: ‘gdb::waitpid’ declared here
75 | waitpid (pid_t pid, int *wstatus, int options)
| ^~~~~~~
...
This is a regression since commit 658a03e9e8 ("[gdbsupport] Add
gdb::{waitpid,read,write,close}"), which moved the use of ::waitpid from
run_under_shell, where it was used conditionally:
...
#if defined(CANT_FORK) || \
(!defined(HAVE_WORKING_VFORK) && !defined(HAVE_WORKING_FORK))
...
#else
...
int ret = gdb::handle_eintr (-1, ::waitpid, pid, &status, 0);
...
to gdb::waitpid, where it's used unconditionally:
...
inline pid_t
waitpid (pid_t pid, int *wstatus, int options)
{
return gdb::handle_eintr (-1, ::waitpid, pid, wstatus, options);
}
...
Likewise for ::wait.
Guard these uses with HAVE_WAITPID and HAVE_WAIT.
Reproduced and tested by doing a mingw-w64 cross-build on x86_64-linux.
Reported-By: Simon Marchi <simark@simark.ca>
Co-Authored-By: Tom de Vries <tdevries@suse.de>
This makes the lists easier sort read and modify. There are no changes
in the generated config.h files, so I'm confident this brings no
functional changes.
Change-Id: Ib6b7fc532bcd662af7dbb230070fb1f4fc75f86b
Eli mentioned [1] that given that we use US English spelling in our
documentation, we should use "behavior" instead of "behaviour".
In wikipedia-common-misspellings.txt there's a rule:
...
behavour->behavior, behaviour
...
which leaves this as a choice.
Add an overriding rule to hardcode the choice to common-misspellings.txt:
...
behavour->behavior
...
and add a rule to rewrite behaviour into behavior:
...
behaviour->behavior
...
and re-run spellcheck.sh on gdb*.
Tested on x86_64-linux.
[1] https://sourceware.org/pipermail/gdb-patches/2024-November/213371.html
By default GDB will be printing the hex payload of the ptwrite package as
auxiliary information. To customize this, the user can register a ptwrite
filter function in python, that takes the payload and the PC as arguments and
returns a string which will be printed instead. Registering the filter
function is done using a factory pattern to make per-thread filtering easier.
Approved-By: Markus Metzger <markus.t.metzger@intel.com>
Now that all known uses of VLAs within GDB are removed, remove the
`-Wno-vla-cxx-extension` (which was used to silence clang warnings) and
add `-Wvla`, such that any use of a VLA will trigger a warning.
Change-Id: I69a8d7f93f973743165b0ba46f9c2ea8adb89025
Reviewed-By: Keith Seitz <keiths@redhat.com>
Currently, if you configure gdb with explicit --enable-threading, but
then configure detects std::thread does not work, configure silently
disables threading support and continues configuring.
This patch makes that scenario cause a configuration error, like so:
$ /home/pedro/gdb/src/configure --enable-threading && make
...
configure: error: std::thread does not work; disable threading
make[1]: *** [Makefile:11225: configure-gdbsupport] Error 1
make[1]: Leaving directory '/home/pedro/gdb/build-windows-threads'
make: *** [Makefile:1041: all] Error 2
$
Additionally, if you don't explicitly pass --enable-threading, and
std::thread does not work, we will now get a warning (and the build
continues):
$ /home/pedro/gdb/src/configure && make
...
configure: WARNING: std::thread does not work; disabling threading
...
This is similar to how we handle --enable-tui and missing curses. The
code and error/warning messages were borrowed from there.
Change-Id: I73a8b580d1e2a796b23136920c0e181408ae1b22
Approved-By: Tom Tromey <tom@tromey.com>
With a x86_64-pc-mingw32 toolchain there is a build issue
whether or not the --disable-threading option is used.
The problem happens because _WIN32_WINNT is defined to 0x501
before #include <mutex> which makes the compilation abort
due to missing support for __gthread_cond_t in std_mutex.h,
which is conditional on _WIN32_WINNT >= 0x600.
Fix the case when --disable-threading is used, by only
including <mutex> in gdb/complaints.c when STD_CXX_THREAD
is defined.
Additionally make the configure script try to #include <mutex>
to automatically select --disable-threading when the header file
is not able to compile.
Approved-By: Tom Tromey <tom@tromey.com>
When building with clang 18, I see:
CXX aarch64-linux-tdep.o
/home/smarchi/src/binutils-gdb/gdb/aarch64-linux-tdep.c:1299:26: error: variable length arrays in C++ are a Clang extension [-Werror,-Wvla-cxx-extension]
1299 | gdb_byte za_zeroed[za_bytes];
| ^~~~~~~~
/home/smarchi/src/binutils-gdb/gdb/aarch64-linux-tdep.c:1299:26: note: read of non-const variable 'za_bytes' is not allowed in a constant expression
/home/smarchi/src/binutils-gdb/gdb/aarch64-linux-tdep.c:1282:10: note: declared here
1282 | size_t za_bytes = std::pow (sve_vl_from_vg (svg), 2);
| ^
Since we are using VLAs right now, that warning doesn't make sense for
us. add `-Wno-vla-cxx-extension` to the list of warning flags we try to
enable. If we ever choose to disallow VLAs, we can remove that flag.
Change-Id: Ie41feafc50c343f6e75333d4f836ce32fbeb6d8c
This changes the various gdb-related directories to use
-Wimplicit-fallthrough=5, meaning that only the fallthrough attribute
can be used in switches -- special 'fallthrough' comments will no
longer be usable.
Approved-By: Pedro Alves <pedro@palves.net>
This patch proposes to require a C++17 compiler to build gdb /
gdbsupport / gdbserver. Before this patch, GDB required a C++11
compiler.
The general policy regarding bumping C++ language requirement in GDB (as
stated in [1]) is:
Our general policy is to wait until the oldest compiler that
supports C++NN is at least 3 years old.
Rationale: We want to ensure reasonably widespread compiler
availability, to lower barrier of entry to GDB contributions, and to
make it easy for users to easily build new GDB on currently
supported stable distributions themselves. 3 years should be
sufficient for latest stable releases of distributions to include a
compiler for the standard, and/or for new compilers to appear as
easily installable optional packages. Requiring everyone to build a
compiler first before building GDB, which would happen if we
required a too-new compiler, would cause too much inconvenience.
See the policy proposal and discussion
[here](https://sourceware.org/ml/gdb-patches/2016-10/msg00616.html).
The first GCC release which with full C++17 support is GCC-9[2],
released in 2019[3], which is over 4 years ago. Clang has had C++17
support since Clang-5[4] released in 2018[5].
A discussions with many distros showed that a C++17-able compiler is
always available, meaning that this no hard requirement preventing us to
require it going forward.
[1] https://sourceware.org/gdb/wiki/Internals%20GDB-C-Coding-Standards#When_is_GDB_going_to_start_requiring_C.2B-.2B-NN_.3F
[2] https://gcc.gnu.org/projects/cxx-status.html#cxx17
[3] https://gcc.gnu.org/gcc-9/
[4] https://clang.llvm.org/cxx_status.html
[5] https://releases.llvm.org/
Change-Id: Id596f5db17ea346e8a978668825787b3a9a443fd
Reviewed-By: Eli Zaretskii <eliz@gnu.org>
Approved-By: Tom Tromey <tom@tromey.com>
Approved-By: Pedro Alves <pedro@palves.net>
A user pointed out that the -lsocket check in gdb should also apply to
gdbserver -- otherwise it can't find the Solaris socketpair. This
patch makes the change. It also removes a couple of redundant
function checks from gdb's configure.ac.
This was tested by the person who reported the bug.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=30927
Approved-By: Pedro Alves <pedro@palves.net>
GCC recently added support for the Windows thread model, enabling
libstdc++ to support Windows natively. However, this supporrt
requires a version of Windows later than the minimum version that is
supported by GDB.
PR build/29966 points out that the GDB configure test for std::thread
does not work in this situation, because _WIN32_WINNT is not defined
in test program, and so <thread> seems to be fine.
This patch is an attempt to fix the problem, by using the same setting
for _WIN32_WINNT at configure time as is used at build time.
I don't have access to one of the older systems so I don't think I can
truly test this. I did do a mingw cross build, though. I'm going to
ask the bug reporter to test it.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29966
The following patch moves the fast_hash function, which uses libxxhash,
to gdbsupport. Move the libxxhash configure check to gdbsupport (and
transitively to gdbserver).
Change-Id: I242499e50c8cd6fe9f51e6e92dc53a1b3daaa96e
Approved-By: Andrew Burgess <aburgess@redhat.com>
I get this diff when re-generating configure, probably leftover from
67d1991b78 ("egrep in binutils").
Change-Id: I759c88c2bad648736d33ff98089db45c9b686356
Commit 171fba11ab ("Make GDBserver abort on internal error in development mode")
created a new substitution CONFIG_STATUS_DEPENDENCIES but this is used by
Makefile.in (which is not regenerated by that commit). After regenerating
it, it is found that CONFIG_STATUS_DEPENDENCIES value is not valid, making
gdbsupport fail to build.
Since the CONFIG_STATUS_DEPENDENCIES value is used in the Makefile, macro
substitution must have a Makefile format but commit 171fba11ab used shell
format "$srcdir/../bfd/development.sh".
This commit fixes this issue by substituting "$srcdir" (shell format) to
"$(srcdir)" (Makefile format). It preserves the dependency as Pedro
intended and fixes the build problem.
It also regenerates corresponding files with the maintainer mode.
gdbsupport/ChangeLog:
* configure.ac: Fix config.status dependency.
* Makefile.in: Regenerate.
* configure: Regenerate.
Currently, if GDBserver hits some internal assertion, it exits with
error status, instead of aborting. This makes it harder to debug
GDBserver, as you can't just debug a core file if GDBserver fails an
assertion. I've had to hack the code to make GDBserver abort to debug
something several times before.
I believe the reason it exits instead of aborting, is to prevent
potentially littering the filesystem of smaller embedded targets with
core files. I think I recall Daniel Jacobowitz once saying that many
years ago, but I can't be sure. Anyhow, that seems reasonable to me.
Since we nowadays have a distinction between development and release
modes, I propose to make GDBserver abort on internal error if in
development mode, while keeping the status quo when in release mode.
Thus, after this patch, in development mode, you get:
$ ../gdbserver/gdbserver
../../src/gdbserver/server.cc:3711: A problem internal to GDBserver has been detected.
captured_main: Assertion `0' failed.
Aborted (core dumped)
$
while in release mode, you'll continue to get:
$ ../gdbserver/gdbserver
../../src/gdbserver/server.cc:3711: A problem internal to GDBserver has been detected.
captured_main: Assertion `0' failed.
$ echo $?
1
I do not think that this requires a separate configure switch.
A "--target_board=native-extended-gdbserver" run on Ubuntu 20.04 ends
up with:
=== gdb Summary ===
# of unexpected core files 29
...
for me, of which 8 are GDBserver core dumps, 7 more than without this
patch.
Change-Id: I6861e08ad71f65a0332c91ec95ca001d130b0e9d
Currently, the configure check for std::thread relies on pthreads
existing. However, this means that if std::thread is implemented for
a non-pthreads host, then the check will yield the wrong answer. This
happened in AdaCore internal builds. Here, we have this GCC patch:
https://gcc.gnu.org/legacy-ml/gcc-patches/2019-06/msg01840.html
... which adds mingw support to GCC's gthreads implementation, and
also to std::thread.
This configure change fixes this problem and enables threading for
gdb.
This pulls out the implementation of an event pipe used to implement
target async support in both linux-low.cc (gdbserver) and linux-nat.c
(gdb).
This will be used to replace the existing event pipe in linux-low.cc
and linux-nat.c in future commits.
Co-Authored-By: Lancelot SIX <lsix@lancelotsix.com>
This commit aims to not make use of -Wmissing-prototypes when
compiling with g++.
Use of -Wmissing-prototypes was added with this commit:
commit a0761e34f0
Date: Wed Mar 11 15:15:12 2020 -0400
gdb: enable -Wmissing-prototypes warning
Because clang can provide helpful warnings with this flag.
Unfortunately, g++ doesn't accept this flag, and will give this
warning:
cc1plus: warning: command line option ‘-Wmissing-prototypes’ is valid for C/ObjC but not for C++
In theory the fact that this flag is not supported should be detected
by the configure check in gdbsupport/warning.m4, but for users of
ccache, this check doesn't work due to a long standing ccache issue:
https://github.com/ccache/ccache/issues/738
The ccache problem is that -W... options are reordered on the command
line, and so -Wmissing-prototypes is seen before -Werror. Usually
this doesn't matter, but the above warning (about the flag not being
valid) is issued before the -Werror flag is processed, and so is not
fatal.
There have been two previous attempts to fix this that I'm aware of.
The first is:
https://sourceware.org/pipermail/gdb-patches/2021-September/182148.html
In this attempt, instead of just relying on a compile to check if a
flag is valid, the proposal was to both compile and link. As linking
doesn't go through ccache, we don't suffer from the argument
reordering problem, and the link phase will correctly fail when using
-Wmissing-prototypes with g++. The configure script will then disable
the use of this flag.
This approach was rejected, and the suggestion was to only add the
-Wmissing-prototypes flag if we are compiling with gcc.
The second attempt, attempts this approach, and can be found here:
https://sourceware.org/pipermail/gdb-patches/2021-November/183076.html
This attempt only adds the -Wmissing-prototypes flag is the value of
GCC is not 'yes'. This feels like it is doing the right thing,
unfortunately, the GCC flag is really a 'is gcc like' flag, not a
strict, is gcc check. As such, GCC is set to 'yes' for clang, which
would mean the flag was not included for clang or gcc. The entire
point of the original commit was to add this flag for clang, so
clearly the second attempt is not sufficient either.
In this new attempt I have added gdbsupport/compiler-type.m4, this
file defines AM_GDB_COMPILER_TYPE. This macro sets the variable
GDB_COMPILER_TYPE to either 'gcc', 'clang', or 'unknown'. In future
the list of values might be extended to cover other compilers, if this
is ever useful.
I've then modified gdbsupport/warning.m4 to only add the problematic
-Wmissing-prototypes flag if GDB_COMPILER_TYPE is not 'gcc'.
I've tested this with both gcc and clang and see the expected results,
gcc no longer attempts to use the -Wmissing-prototypes flag, while
clang continues to use it.
When compiling using ccache, I am no longer seeing the warning.
Add the --enable-threading configure option so multithreading can be disabled
at configure time. This is useful for statically-linked builds of
GDB/GDBserver, since the thread library doesn't play well with that setup.
If you try to run a statically-linked GDB built with threading, it will crash
when setting up the number of worker threads.
This new option is also convenient when debugging GDB in a system with lots of
threads, where the thread discovery code in GDB will emit too many messages,
like so:
[New Thread 0xfffff74d3a50 (LWP 2625599)]
If you have X threads, that message will be repeated X times.
The default for --enable-threading is "yes".
The rhES5 build failed due to an upstream import a while back. The
bug here is that, while the 'personality' function exists,
ADDR_NO_RANDOMIZE is only defined in <linux/personality.h>, not
<sys/personality.h>.
However, <linux/personality.h> does not declare the 'personality'
function, and <sys/personality.h> and <linux/personality.h> cannot
both be included.
This patch restores one of the removed configure checks and updates
the code to check it.
We had this as a local patch at AdaCore, because it seemed like there
was no interest upstream. However, now it turns out that this fixes
PR build/28555, so I'm sending it now.
The format_pieces selftest currently fails on Windows hosts.
The selftest doesn't handle the "%ll" -> "%I64" rewrite that the
formatter may perform, but also gdbsupport was missing a configure
check for PRINTF_HAS_LONG_LONG. This patch fixes both issues.
Say we use a gcc version that (while supporting c++11) does not support c++11
by default, and needs an -std setting to enable it.
If gdb would use the default AX_CXX_COMPILE_STDCXX from autoconf-archive, then
we'd have:
...
CXX="g++ -std=gnu++11"
...
That mechanism however has the following problem (quoting from commit
0bcda68539):
...
the top level Makefile passes CXX down to subdirs, and that overrides whatever
gdb/Makefile may set CXX to. The result would be that a make invocation from
the build/gdb/ directory would use "g++ -std=gnu++11" as expected, while a
make invocation at the top level would not.
...
Commit 0bcda68539 fixes this by using a custom AX_CXX_COMPILE_STDCXX which
does:
...
CXX=g++
CXX_DIALECT=-std=gnu++11
...
The problem reported in PR28318 is that using the custom instead of the
default AX_CXX_COMPILE_STDCXX makes the configure test for std::thread
support fail.
We could simply add $CXX_DIALECT to the test for std::thread support, but
that would have to be repeated for each added c++ support test.
Instead, fix this by doing:
...
CXX="g++ -std=gnu++11"
CXX_DIALECT=-std=gnu++11
...
This is somewhat awkward, since it results in -std=gnu++11 occuring twice in
some situations:
...
$ touch src/gdb/dwarf2/read.c
$ ( cd build/gdb; make V=1 dwarf2/read.o )
g++-4.8 -std=gnu++11 -x c++ -std=gnu++11 ...
...
However, both settings are needed:
- the switch in CXX for the std::thread tests (and other tests)
- the switch in CXX_DIALECT so it can be appended in Makefiles, to
counteract the fact that the top-level Makefile overrides CXX
The code added in gdb/ax_cxx_compile_stdcxx.m4 is copied from the default
AX_CXX_COMPILE_STDCXX from autoconf-archive.
Tested on x86_64-linux.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=28318
In the gdbsupport configure.ac file, there is an attempt to define
TARGET_WORD_SIZE. This is done by running grep on the file
../bfd/bfd-in3.h.
The problem with this is, the file bfd-in3.h is generated into the bfd
build directory when bfd is configured, and there is no dependency
between the gdbsupport module and the bfd module, so, for example, if
I do:
$ ../src/configure
$ make all-gdbsupport
Then bfd will neither be configured, or built. In this case
TARGET_WORD_SIZE ends up being defined, but with no value because the
grep on bfd-in3.h fails.
However, it turns out that this doesn't matter; we don't actually use
TARGET_WORD_SIZE anywhere.
My proposal in this commit is to just remove the definition of
TARGET_WORD_SIZE, the alternative would be to add a dependency between
configure-gdbsupport and configure-bfd into Makefile.def, but adding a
dependency for something we don't need seems pretty pointless.
The next patch will make the use of sigtimedwait conditional to whether
the platform provides it. Start by adding a configure check for it.
gdbsupport/ChangeLog:
* common.m4 (GDB_AC_COMMON): Check for sigtimedwait.
* config.in, configure: Re-generate.
gdb/ChangeLog:
* config.in, configure: Re-generate.
gdbserver/ChangeLog:
* config.in, configure: Re-generate.
Change-Id: Ic7613fe14521b966b4d991bbcd0933ab14629c05
I get these changes when re-generating the autoconf stuff in gdbsupport,
fallouts from 4655f8509f ("Don't run personality syscall at configure
time; don't check it at all").
gdbsupport/ChangeLog:
* Makefile.in: Re-generate.
* config.in: Re-generate.
* configure: Re-generate.
Change-Id: Ie1876ee58d6f4f1cf25fa14900eecf4c85a744c1
For some reason, autoupdate isn't able to grok ptrace.m4:
$ autoupdate ptrace.m4
/usr/bin/m4:/tmp/auYjuodw/input.m4:171: ERROR: end of file in string
autoupdate: /usr/bin/m4 failed with exit status: 1
Honestly, I'm unable to grok it either. This patch re-indents it in a
way that I think is easier to read. With this patch applied, autoupdate
becomes able to parse ptrace.m4, but I chose to keep this re-indent in a
patch of its own.
All the changes in generated configure files consist of insignificant
whitespace changes.
gdb/ChangeLog:
* configure: Re-generate.
gdbserver/ChangeLog:
* configure: Re-generate.
gdbsupport/ChangeLog:
* configure: Re-generate.
* ptrace.m4: Re-indent.
Change-Id: Ie2afab09fecc8b6d0cccccb47ac9756f3843881e
`autoconf -Wall` notes that AM_PROG_CC_STDC is obsolete:
Fixes this autoconf warning:
configure.ac:40: warning: 'AM_PROG_CC_STDC': this macro is obsolete.
configure.ac:40: You should simply use the 'AC_PROG_CC' macro instead.
configure.ac:40: Also, your code should no longer depend upon 'am_cv_prog_cc_stdc',
configure.ac:40: but upon 'ac_cv_prog_cc_stdc'.
aclocal.m4:770: AM_PROG_CC_STDC is expanded from...
configure.ac:40: the top level
Since we build with a C++ compiler now, I don't think this is relevant.
If you look at the messages removed from gdbsupport/aclocal.m4, it says
that this functionality is now integrated in AC_PROG_CC, which we
already call. So it might not even make a difference.
We had a local version of AM_PROG_CC_STDC, in gdb/acinclude.m4 (only
used by gdb/configure.ac), remove it.
gdb/ChangeLog:
* acinclude.m4 (AM_PROG_CC_STDC): Remove.
* configure: Re-generate.
* configure.ac: Remove AM_PROG_CC_STDC.
gdbsupport/ChangeLog:
* aclocal.m4: Re-generate.
* configure: Re-generate.
* configure.ac: Remove AM_PROG_CC_STDC.
Change-Id: Ic824393598805d4f78cda9d119f8af46096e9c73
`autoreconf -Wall` notes that AC_CANONICAL_SYSTEM is obsolete:
configure.ac:36: warning: The macro `AC_CANONICAL_SYSTEM' is obsolete.
Replace it by AC_CANONICAL_BUILD, AC_CANONICAL_HOST and
AC_CANONICAL_TARGET in configure.ac files in gdb, gdbserver and
gdbsupport. All three macros may not be needed everywhere, but it is
hard to completely audit the configure files to see which are required,
so I think it's better (and that there's no downside) to just call all
three.
gdb/ChangeLog:
* configure.ac: Use AC_CANONICAL_{BUILD,HOST,TARGET} instead of
AC_CANONICAL_SYSTEM.
* configure: Re-generate.
gdbserver/ChangeLog:
* configure.ac: Use AC_CANONICAL_{BUILD,HOST,TARGET} instead of
AC_CANONICAL_SYSTEM.
* configure: Re-generate.
gdbsupport/ChangeLog:
* configure.ac: Use AC_CANONICAL_{BUILD,HOST,TARGET} instead of
AC_CANONICAL_SYSTEM.
* configure: Re-generate.
Change-Id: Ifd0e21f1e478634e768b5de1b8ee06a7f690d863
FreeBSD systems have provided these functions in libutil since 7.1
release. The most recent release without support is 6.4 released in
November of 2008.
This also requires libutil-freebsd on GNU/kFreeBSD systems. I assume
that those systems have supported kinfo_get_file and kinfo_get_vmmap
over a similar timeframe.
gdb/ChangeLog:
* configure.ac: Remove check for kinfo_getvmmap().
* configure, config.in: Regenerate.
* fbsd-nat.c (fbsd_read_mapping): Remove
(fbsd_nat_target::find_memory_regions): Remove the procfs version.
(fbsd_nat_target::info_proc): Assume kinfo_getfile() and
kinfo_get_vmmap() are always present.
gdbsupport/ChangeLog:
* common.m4 (GDB_AC_COMMON): Refactor checks for kinfo_getfile().
* configure, config.in: Regenerate.
GDB currently doesn't build on 32-bit Solaris:
* On Solaris 11.4/x86:
In file included from /usr/include/sys/procfs.h:26,
from /vol/src/gnu/gdb/hg/master/dist/gdb/i386-sol2-nat.c:24:
/usr/include/sys/old_procfs.h:31:2: error: #error "Cannot use procfs in the large file compilation environment"
#error "Cannot use procfs in the large file compilation environment"
^~~~~
* On Solaris 11.3/x86 there are several more instances of this.
The interaction between procfs and large-file support historically has
been a royal mess on Solaris:
* There are two versions of the procfs interface:
** The old ioctl-based /proc, deprecated and not used any longer in
either gdb or binutils.
** The `new' (introduced in Solaris 2.6, 1997) structured /proc.
* There are two headers one can possibly include:
** <procfs.h> which only provides the structured /proc, definining
_STRUCTURED_PROC=1 and then including ...
** <sys/procfs.h> which defaults to _STRUCTURED_PROC=0, the ioctl-based
/proc, but provides structured /proc if _STRUCTURED_PROC == 1.
* procfs and the large-file environment didn't go well together:
** Until Solaris 11.3, <sys/procfs.h> would always #error in 32-bit
compilations when the large-file environment was active
(_FILE_OFFSET_BITS == 64).
** In both Solaris 11.4 and Illumos, this restriction was lifted for
structured /proc.
So one has to be careful always to define _STRUCTURED_PROC=1 when
testing for or using <sys/procfs.h> on Solaris. As the errors above
show, this isn't always the case in binutils-gdb right now.
Also one may need to disable large-file support for 32-bit compilations
on Solaris. config/largefile.m4 meant to do this by wrapping the
AC_SYS_LARGEFILE autoconf macro with appropriate checks, yielding
ACX_LARGEFILE. Unfortunately the macro doesn't always succeed because
it neglects the _STRUCTURED_PROC part.
To make things even worse, since GCC 9 g++ predefines
_FILE_OFFSET_BITS=64 on Solaris. So even if largefile.m4 deciced not to
enable large-file support, this has no effect, breaking the gdb build.
This patch addresses all this as follows:
* All tests for the <sys/procfs.h> header are made with
_STRUCTURED_PROC=1, the definition going into the various config.h
files instead of having to make them (and sometimes failing) in the
affected sources.
* To cope with the g++ predefine of _FILE_OFFSET_BITS=64,
-U_FILE_OFFSET_BITS is added to various *_CPPFLAGS variables. It had
been far easier to have just
#undef _FILE_OFFSET_BITS
in config.h, but unfortunately such a construct in config.in is
commented by config.status irrespective of indentation and whitespace
if large-file support is disabled. I found no way around this and
putting the #undef in several global headers for bfd, binutils, ld,
and gdb seemed way more invasive.
* Last, the applicability check in largefile.m4 was modified only to
disable largefile support if really needed. To do so, it checks if
<sys/procfs.h> compiles with _FILE_OFFSET_BITS=64 defined. If it
doesn't, the disabling only happens if gdb exists in-tree and isn't
disabled, otherwise (building binutils from a tarball), there's no
conflict.
What initially confused me was the check for $plugins here, which
originally caused the disabling not to take place. Since AC_PLUGINGS
does enable plugin support if <dlfcn.h> exists (which it does on
Solaris), the disabling never happened.
I could find no explanation why the linker plugin needs large-file
support but thought it would be enough if gld and GCC's lto-plugin
agreed on the _FILE_OFFSET_BITS value. Unfortunately, that's not
enough: lto-plugin uses the simple-object interface from libiberty,
which includes off_t arguments. So to fully disable large-file
support would mean also disabling it in libiberty and its users: gcc
and libstdc++-v3. This seems highly undesirable, so I decided to
disable the linker plugin instead if large-file support won't work.
The patch allows binutils+gdb to build on i386-pc-solaris2.11 (both
Solaris 11.3 and 11.4, using GCC 9.3.0 which is the worst case due to
predefined _FILE_OFFSET_BITS=64). Also regtested on
amd64-pc-solaris2.11 (again on Solaris 11.3 and 11.4),
x86_64-pc-linux-gnu and i686-pc-linux-gnu.
config:
* largefile.m4 (ACX_LARGEFILE) <sparc-*-solaris*|i?86-*-solaris*>:
Check for <sys/procfs.h> incompatilibity with large-file support
on Solaris.
Only disable large-file support and perhaps plugins if needed.
Set, substitute LARGEFILE_CPPFLAGS if so.
bfd:
* bfd.m4 (BFD_SYS_PROCFS_H): New macro.
(BFD_HAVE_SYS_PROCFS_TYPE): Require BFD_SYS_PROCFS_H.
Don't define _STRUCTURED_PROC.
(BFD_HAVE_SYS_PROCFS_TYPE_MEMBER): Likewise.
* elf.c [HAVE_SYS_PROCFS_H] (_STRUCTURED_PROC): Don't define.
* configure.ac: Use BFD_SYS_PROCFS_H to check for <sys/procfs.h>.
* configure, config.in: Regenerate.
* Makefile.am (AM_CPPFLAGS): Add LARGEFILE_CPPFLAGS.
* Makefile.in, doc/Makefile.in: Regenerate.
binutils:
* Makefile.am (AM_CPPFLAGS): Add LARGEFILE_CPPFLAGS.
* Makefile.in, doc/Makefile.in: Regenerate.
* configure: Regenerate.
gas:
* Makefile.am (AM_CPPFLAGS): Add LARGEFILE_CPPFLAGS.
* Makefile.in, doc/Makefile.in: Regenerate.
* configure: Regenerate.
gdb:
* proc-api.c (_STRUCTURED_PROC): Don't define.
* proc-events.c: Likewise.
* proc-flags.c: Likewise.
* proc-why.c: Likewise.
* procfs.c: Likewise.
* Makefile.in (INTERNAL_CPPFLAGS): Add LARGEFILE_CPPFLAGS.
* configure, config.in: Regenerate.
gdbserver:
* configure, config.in: Regenerate.
gdbsupport:
* Makefile.am (AM_CPPFLAGS): Add LARGEFILE_CPPFLAGS.
* common.m4 (GDB_AC_COMMON): Use BFD_SYS_PROCFS_H to check for
<sys/procfs.h>.
* Makefile.in: Regenerate.
* configure, config.in: Regenerate.
gnulib:
* configure.ac: Run ACX_LARGEFILE before gl_EARLY.
* configure: Regenerate.
gprof:
* Makefile.am (AM_CPPFLAGS): Add LARGEFILE_CPPFLAGS.
* Makefile.in: Regenerate.
* configure: Regenerate.
ld:
* Makefile.am (AM_CPPFLAGS): Add LARGEFILE_CPPFLAGS.
* Makefile.in: Regenerate.
* configure: Regenerate.
gdb_select.h and the event loop require some configure checks, so this
moves the needed checks to common.m4 and updates the configure
scripts.
gdb/ChangeLog
2020-04-13 Tom Tromey <tom@tromey.com>
* configure: Rebuild.
* configure.ac: Remove checks that are now in GDB_AC_COMMON.
gdbserver/ChangeLog
2020-04-13 Tom Tromey <tom@tromey.com>
* configure: Rebuild.
* config.in: Rebuild.
gdbsupport/ChangeLog
2020-04-13 Tom Tromey <tom@tromey.com>
* config.in, configure: Rebuild.
* common.m4 (GDB_AC_COMMON): Check for poll.h, sys/poll.h,
sys/select.h, and poll.
I stumbled on this snippet in nat/gdb_ptrace.h:
/* Some systems, in particular DEC OSF/1, Digital Unix, Compaq Tru64
or whatever it's called these days, don't provide a prototype for
ptrace. Provide one to silence compiler warnings. */
#ifndef HAVE_DECL_PTRACE
extern PTRACE_TYPE_RET ptrace();
#endif
I believe this is unnecessary today and should be removed. First, the
comment only mentions OSes we don't support (and to be honest, I had
never even heard of).
But most importantly, in C++, a declaration with empty parenthesis
declares a function that accepts no arguments, unlike in C. So if this
declaration was really used, GDB wouldn't build, since all ptrace call
sites pass some arguments. Since we haven't heard anything about this
causing some build failures since we have transitioned to C++, I
conclude that it's not used.
This patch removes it as well as the corresponding configure check.
gdb/ChangeLog:
* ptrace.m4: Don't check for ptrace declaration.
* config.in: Re-generate.
* configure: Re-generate.
* nat/gdb_ptrace.h: Don't declare ptrace if HAVE_DECL_PTRACE is
not defined.
gdbserver/ChangeLog:
* config.in: Re-generate.
* configure: Re-generate.
gdbsupport/ChangeLog:
* config.in: Re-generate.
* configure: Re-generate.
The same is done for gdb, gdbserver and gdbsupport. I therefore think
it makes sense to move that to GDB_AC_COMMON.
It is required to move the call to GDB_AC_COMMON so it is before
GDB_AC_SELFTEST in gdbserver/configure.ac, otherwise the $development
variable isn't set when the code behind GDB_AC_SELFTEST executes.
gdb/ChangeLog:
* configure.ac: Don't source bfd/development.sh.
* selftest.m4: Modify comment.
* configure: Re-generate.
gdbserver/ChangeLog:
* configure.ac: Don't source bfd/development.sh, move
GDB_AC_COMMON higher.
* configure: Re-generate.
gdbsupport/ChangeLog:
* configure.ac: Don't source bfd/development.sh.
* common.m4: Source bfd/development.sh.
* configure: Re-generate.
Before commit 3d1e5a43cb ("gdbsupport/configure.ac: source
development.sh"), the GDB build in non-development mode (turn
development to false in bfd/development.sh if you want to try) was
broken because the gdbsupport configure script didn't source
bfd/development.sh to set the development variable.
Since the GDB_AC_SELFTEST macro relies on the `development` variable, I
propose to modify it such that it errors out if $development does not
have an expected value of "true" or "false". This could prevent a
future similar problem from happening while refactoring the configure
scripts. It would have caught the problem fixed by the patch mentioned
earlier.
gdb/ChangeLog:
* selftest.m4 (GDB_AC_SELFTEST): Error out if $development is
not "true" or "false".
* configure: Re-generate.
gdbserver/ChangeLog:
* configure: Re-generate.
gdbsupport/ChangeLog:
* configure: Re-generate.
While compiling with clang, I noticed it didn't catch cases where my
function declaration didn't match my function definition. This is
normally caught by gcc with -Wmissing-declarations.
On clang, this is caught by -Wmissing-prototypes instead.
Note that on gcc, -Wmissing-prototypes also exists, but is only valid
for C and Objective-C. It gets correctly rejected by the configure
script since gcc rejects it with:
cc1plus: error: command line option '-Wmissing-prototypes' is valid for C/ObjC but not for C++ -Werror
So this warning flag ends up not used for gcc (which is what we want).
gdb/ChangeLog:
* configure: Re-generate.
gdbserver/ChangeLog:
* configure: Re-generate.
gdbsupport/ChangeLog:
* configure: Re-generate.
* warning.m4: Enable -Wmissing-prototypes.
[Commit message by Simon Marchi]
The GDB build in non-development mode (turn development to false in
bfd/development.sh if you want to try) is currently broken:
CXXLD gdb
/home/smarchi/src/binutils-gdb/gdb/disasm-selftests.c:218: error: undefined reference to 'selftests::register_test_foreach_arch(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, void (*)(gdbarch*))'
/home/smarchi/src/binutils-gdb/gdb/disasm-selftests.c:220: error: undefined reference to 'selftests::register_test_foreach_arch(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, void (*)(gdbarch*))'
/home/smarchi/src/binutils-gdb/gdb/dwarf2/frame.c:2310: error: undefined reference to 'selftests::register_test_foreach_arch(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, void (*)(gdbarch*))'
/home/smarchi/src/binutils-gdb/gdb/gdbarch-selftests.c:168: error: undefined reference to 'selftests::register_test_foreach_arch(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, void (*)(gdbarch*))'
/home/smarchi/src/binutils-gdb/gdbsupport/selftest.cc:96: error: undefined reference to 'selftests::reset()'
This is because the gdbsupport configure script doesn't source
bfd/development.sh to set the development variable. When $development
is unset, GDB_AC_SELFTEST defaults to enabling selftests. I don't think
the macro was written with this intention in mind, it just happens to be
that way.
So gdbsupport thinks selftests are enabled, while gdb thinks they are
disabled. gdbsupport compiles in code that calls selftests:: functions,
which are normally provided by gdb, but gdb doesn't provide them, hence
the undefined references.
Fix this by sourcing bfd/development.sh in gdbsupport/configure.ac, so
that the development variable is set.
gdbsupport/ChangeLog:
* configure.ac: Added call development.sh.
* configure: Regenerate.
