From c8693053f895626ae90b7856d3738de47d14d52c Mon Sep 17 00:00:00 2001 From: Rainer Orth Date: Thu, 30 Jul 2020 15:41:50 +0200 Subject: 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: ** which only provides the structured /proc, definining _STRUCTURED_PROC=1 and then including ... ** 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, 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 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 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 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 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) : Check for 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 . * 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 . * 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. --- config/ChangeLog | 8 ++++++++ config/largefile.m4 | 45 +++++++++++++++++++++++++++++++++------------ 2 files changed, 41 insertions(+), 12 deletions(-) (limited to 'config') diff --git a/config/ChangeLog b/config/ChangeLog index f93d86a..ba1fc7f 100644 --- a/config/ChangeLog +++ b/config/ChangeLog @@ -1,3 +1,11 @@ +2020-07-30 Rainer Orth + + * largefile.m4 (ACX_LARGEFILE) : + Check for incompatilibity with large-file support + on Solaris. + Only disable large-file support and perhaps plugins if needed. + Set, substitute LARGEFILE_CPPFLAGS if so. + 2020-07-28 H.J. Lu PR binutils/26301 diff --git a/config/largefile.m4 b/config/largefile.m4 index 4a88fd7..9375963 100644 --- a/config/largefile.m4 +++ b/config/largefile.m4 @@ -1,5 +1,5 @@ # This macro wraps AC_SYS_LARGEFILE with one exception for Solaris. -# PR 9992/binutils: We have to replicate everywhere the behaviour of +# PR binutils/9992: We have to replicate everywhere the behaviour of # bfd's configure script so that all the directories agree on the size # of structures used to describe files. @@ -16,17 +16,38 @@ AC_REQUIRE([AC_CANONICAL_TARGET]) AC_PLUGINS case "${host}" in -changequote(,)dnl - sparc-*-solaris*|i[3-7]86-*-solaris*) -changequote([,])dnl - # On native 32bit sparc and ia32 solaris, large-file and procfs support - # are mutually exclusive; and 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. - test "${target}" = "${host}" -a "x$plugins" = xno \ - && : ${enable_largefile="no"} + sparc-*-solaris*|i?86-*-solaris*) + # On native 32-bit Solaris/SPARC and x86, large-file and procfs support + # were mutually exclusive until Solaris 11.3. Without procfs support, + # the bfd/ elf module cannot provide certain routines such as + # elfcore_write_prpsinfo or elfcore_write_prstatus. So unless the user + # explicitly requested large-file support through the + # --enable-largefile switch, disable large-file support in favor of + # procfs support. + # + # Check if is incompatible with large-file support. + AC_TRY_COMPILE([#define _FILE_OFFSET_BITS 64 +#define _STRUCTURED_PROC 1 +#include ], , acx_cv_procfs_lfs=yes, acx_cv_procfs_lfs=no) + # + # Forcefully disable large-file support only if necessary, gdb is in + # tree and enabled. + if test "${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 ;; esac -- cgit v1.1