Make gdbserver's build system locate libiconv when building for Linux.
Commit 07b3255c3b ("Filter invalid encodings from Linux thread names")
make libiconv madantory for building gdbserver on Linux.
While trying to cross-compile gdb for xtensa-fsf-linux-uclibc (with a
toolchain generated with crosstool-ng), I got:
/home/smarchi/src/binutils-gdb/gdbserver/linux-low.cc:48:10: fatal error: iconv.h: No such file or directory
48 | #include <iconv.h>
| ^~~~~~~~~
I downloaded GNU libiconv, built it for that host, and installed it in
an arbitrary directory. I had to modify the gdbserver build system to
locate libiconv and use it, the result is this patch.
I eventually found that crosstool-ng has a config option to make uclibc
provide an implementation of iconv, which is of course much easier. But
given that this patch is now written, I think it would be worth merging
it, it could help some people who do not have iconv built-in their libc
in the future (and may not have the luxury of rebuilding their libc like
I do).
Using AM_ICONV in configure.ac adds these options for configure (the
same we have for gdb):
--with-libiconv-prefix[=DIR] search for libiconv in DIR/include and DIR/lib
--without-libiconv-prefix don't search for libiconv in includedir and libdir
--with-libiconv-type=TYPE type of library to search for (auto/static/shared)
It sets the `LIBICONV` variable with whatever is needed to link with
libiconv, and adds the necessary `-I` flag to `CPPFLAGS`.
To avoid unnecessarily linking against libiconv on hosts that don't need
it, set `MAYBE_LIBICONV` with the contents of `LIBICONV` only if the
host is Linux, and use `MAYBE_LIBICONV` in `Makefile.in`.
Since libiconv is a hard requirement for Linux hosts, error out if it is
not found.
The bits in acinclude.m4 are similar to what we have in
gdb/acinclude.m4.
Update the top-level build system to support building against an in-tree
libiconv (I did not test this part though). Something tells me that the
all-gdbserver dependency on all-libiconv is unnecessary, since there is
already a dependency of configure-gdbserver on all-libiconv (and
all-gdbserver surely depends on configure-gdbserver). I just copied
what's done for GDB though.
ChangeLog:
* Makefile.def: Add configure-gdbserver and all-gdbserver
dependencies on all-libiconv.
* Makefile.in: Re-generate.
Change-Id: I90f8ef88dd4917df5a68b45550d93622fc9cfed4
Approved-By: Tom Tromey <tom@tromey.com>
This is used by gdb, gdbsupport, and gdbserver. We want to use it
in the sim tree too. Move it to gdbsupport which is meant as the
common sharing space for these projects.
Approved-By: Tom Tromey <tom@tromey.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.
These dirs don't use automake, so use AC_CONFIG_MACRO_DIRS to specify
../config as a search dir for m4 macros. This allows removal of a lot
of hand-written m4_include's from acinclude.m4 files, and simplifies
use of `aclocal` or `autoreconf` as manual -I is not needed.
... with AC_COMPILE_IFELSE and AC_LANG_PROGRAM.
All changes in the generated configure file are insignificant
whitespace changes.
gdbserver/ChangeLog:
* acinclude.m4: Replace AC_TRY_COMPILE with AC_COMPILE_IFELSE +
AC_LANG_PROGRAM.
* configure: Re-generate.
Change-Id: Idab8b5e1a984046b5283940c02e5a22da2291d58
ptrace.m4, providing the GDB_AC_PTRACE autoconf macro, is used by gdb,
gdbserver and gdbsupport. I think it would make sense to move it to
gdbsupport.
gdb/ChangeLog:
* acinclude.m4: Update ptrace.m4 path.
* ptrace.m4: Moved to gdbsupport.
gdbserver/ChangeLog:
* acinclude.m4: Update ptrace.m4 path.
gdbsupport/ChangeLog:
* Makefile.in: Re-generate.
* acinclude.m4: Update ptrace.m4 path.
* ptrace.m4: Move here.
Change-Id: I849c149fd5dd8c3b2b0af38654fb353e3727871b
gdbserver uses gdb's alloc.c, and this in turn can include headers
from intl via gdbsupport/gdb_locale.h. This can cause build failures
in some situations, for example if you build gdb and gdbserver on
mingw.
This patch restores the gdbsupport dependency on intl, and changes
gdbserver to use ZW_GNU_GETTEXT_SISTER_DIR. This fixes this build
problem.
ChangeLog
2020-03-12 Tom Tromey <tom@tromey.com>
* Makefile.in: Rebuild.
* Makefile.def (gdbsupport): Depend on intl.
gdbserver/ChangeLog
2020-03-12 Tom Tromey <tom@tromey.com>
* config.in, configure: Rebuild.
* configure.ac: Call ZW_GNU_GETTEXT_SISTER_DIR.
* acinclude.m4: Include gettext-sister.m4.
* Makefile.in (top_builddir, INTL, INTL_DEPS, INTL_CFLAGS): New
variables.
(INCLUDE_CFLAGS): Add INTL_CFLAGS.
(gdbserver$(EXEEXT), gdbreplay$(EXEEXT)): Use INTL_DEPS, INTL.
The selftest.m4 file is used by gdb, gdbserver and gdbsupport, I think
it belongs in gdbsupport.
gdb/ChangeLog:
* selftest.m4: Move to gdbsupport/.
* acinclude.m4: Update path to selftest.m4.
gdbserver/ChangeLog:
* acinclude.m4: Update path to selftest.m4.
gdbsupport/ChangeLog:
* selftest.m4: Moved from gdb/.
* acinclude.m4: Update path to selftest.m4.
This changes gdbserver so that it no longer builds its own gnulib and
libiberty. Instead, it now relies on the ones that were already built
at the top level.
gdbsupport is still built specially for gdbserver. This is more
complicated and will be tackled in a subsequent patch.
ChangeLog
2020-02-14 Tom Tromey <tom@tromey.com>
* Makefile.in: Rebuild.
* Makefile.def: Make gdbserver require gnulib and libiberty.
gdbserver/ChangeLog
2020-02-14 Tom Tromey <tom@tromey.com>
* acinclude.m4: Don't include acx_configure_dir.m4.
* Makefile.in (LIBIBERTY_BUILDDIR, GNULIB_BUILDDIR): Update.
(SUBDIRS, CLEANDIRS, REQUIRED_SUBDIRS): Remove.
(all, install-only, uninstall, clean-info, clean)
(maintainer-clean): Don't recurse.
(subdir_do, all-lib): Remove.
($(LIBGNU) $(LIBIBERTY) $(GNULIB_H)): Remove rule.
(GNULIB_H): Remove.
(generated_files): Update.
($(GNULIB_BUILDDIR)/Makefile): Remove rule.
* configure: Rebuild.
* configure.ac: Don't configure gnulib or libiberty.
(GNULIB): Update.
gdbsupport/ChangeLog
2020-02-14 Tom Tromey <tom@tromey.com>
* common-defs.h: Change path to gnulib/config.h.
Change-Id: I469cbbf5db2ab37109c058e9e3a1e4f4dabdfc98
This file is used by gdbsupport, gdbserver and gdb, so I think it
belongs in gdbsupport. Move it there and update the references the
various acinclude.m4 files.
gdbsupport/ChangeLog:
* warning.m4: Move here, from gdb/warning.m4.
* acinclude.m4: Update warning.m4 path.
* Makefile.in: Re-generate.
gdbserver/ChangeLog:
* acinclude.m4: Update warning.m4 path.
gdb/ChangeLog:
* acinclude: Update warning.m4 path.
* warning.m4: Move to gdbsupport.
This patch moves gdbserver to the top level.
This patch is as close to a pure move as possible -- gdbserver still
builds its own variant of gnulib and gdbsupport. Changing this will
be done in a separate patch.
[v2] Note that, per Simon's review comment, this patch changes the
tree so that gdbserver is not built for or1k or score. This makes
sense, because there is apparently not actually a gdbserver port here.
[v3] This version of the patch also splits out some configury into a
new file, gdbserver/configure.host, so that the top-level configure
script can simply rely on it in order to decide whether gdbserver
should be built.
[v4] This version adds documentation and removes some unnecessary
top-level dependencies.
[v5] Update docs to mention "make all-gdbserver" and change how
top-level configure decides whether to build gdbserver, switching to a
single, shared script.
Tested by the buildbot.
ChangeLog
2020-02-07 Tom Tromey <tom@tromey.com>
Pedro Alves <palves@redhat.com>
* src-release.sh (GDB_SUPPORT_DIRS): Add gdbserver.
* gdbserver: New directory, moved from gdb/gdbserver.
* configure.ac (host_tools): Add gdbserver.
Only build gdbserver on certain systems.
* Makefile.in, configure: Rebuild.
* Makefile.def (host_modules, dependencies): Add gdbserver.
* MAINTAINERS: Add gdbserver.
gdb/ChangeLog
2020-02-07 Tom Tromey <tom@tromey.com>
* README: Update gdbserver documentation.
* gdbserver: Move to top level.
* configure.tgt (build_gdbserver): Remove.
* configure.ac: Remove --enable-gdbserver.
* configure: Rebuild.
* Makefile.in (distclean): Don't mention gdbserver.
Change-Id: I826b7565b54604711dc7a11edea0499cd51ff39e
