binutils-gdb/config/largefile.m4

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# This macro wraps AC_SYS_LARGEFILE with one exception for Solaris.
Unify Solaris procfs and largefile handling 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.
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# PR binutils/9992: We have to replicate everywhere the behaviour of
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# bfd's configure script so that all the directories agree on the size
# of structures used to describe files.
AC_DEFUN([ACX_LARGEFILE],[dnl
# The tests for host and target for $enable_largefile require
# canonical names.
AC_REQUIRE([AC_CANONICAL_HOST])
AC_REQUIRE([AC_CANONICAL_TARGET])
# As the $enable_largefile decision depends on --enable-plugins we must set it
# even in directories otherwise not depending on the $plugins option.
AC_PLUGINS
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case "${host}" in
Unify Solaris procfs and largefile handling 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.
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sparc-*-solaris*|i?86-*-solaris*)
# On native 32-bit Solaris/SPARC and x86, large-file and procfs support
# were mutually exclusive until Solaris 11.3. Without procfs support,
# the bfd/ elf module cannot provide certain routines such as
# elfcore_write_prpsinfo or elfcore_write_prstatus. So unless the user
# explicitly requested large-file support through the
# --enable-largefile switch, disable large-file support in favor of
# procfs support.
#
# Check if <sys/procfs.h> is incompatible with large-file support.
AC_TRY_COMPILE([#define _FILE_OFFSET_BITS 64
#define _STRUCTURED_PROC 1
#include <sys/procfs.h>], , acx_cv_procfs_lfs=yes, acx_cv_procfs_lfs=no)
#
# Forcefully disable large-file support only if necessary, gdb is in
# tree and enabled.
if test "${target}" = "${host}" -a "$acx_cv_procfs_lfs" = no \
-a -d $srcdir/../gdb -a "$enable_gdb" != no; then
: ${enable_largefile="no"}
if test "$plugins" = yes; then
AC_MSG_WARN([
plugin support disabled; require large-file support which is incompatible with GDB.])
plugins=no
fi
fi
#
# Explicitly undef _FILE_OFFSET_BITS if enable_largefile=no for the
# benefit of g++ 9+ which predefines it on Solaris.
if test "$enable_largefile" = no; then
LARGEFILE_CPPFLAGS="-U_FILE_OFFSET_BITS"
AC_SUBST(LARGEFILE_CPPFLAGS)
fi
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;;
esac
AC_SYS_LARGEFILE
])