From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 2181) id D24253858034; Fri, 22 Jul 2022 17:44:22 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org D24253858034 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" From: Jonathan Wakely To: gcc-cvs@gcc.gnu.org, libstdc++-cvs@gcc.gnu.org Subject: [gcc r12-8610] libstdc++: check for openat X-Act-Checkin: gcc X-Git-Author: Alexandre Oliva X-Git-Refname: refs/heads/releases/gcc-12 X-Git-Oldrev: 98ce66a48fb01475e011757464c49a3b284ae5da X-Git-Newrev: ca82e7900f40d240f246371c376d0c6fb126b5a0 Message-Id: <20220722174422.D24253858034@sourceware.org> Date: Fri, 22 Jul 2022 17:44:22 +0000 (GMT) X-BeenThere: libstdc++-cvs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libstdc++-cvs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 22 Jul 2022 17:44:22 -0000 https://gcc.gnu.org/g:ca82e7900f40d240f246371c376d0c6fb126b5a0 commit r12-8610-gca82e7900f40d240f246371c376d0c6fb126b5a0 Author: Alexandre Oliva Date: Thu Jun 23 23:20:53 2022 -0300 libstdc++: check for openat rtems6.0 has fdopendir, and fcntl.h defines AT_FDCWD and declares openat, but there's no openat in libc. Adjust dir-common.h to not assume ::openat just because of AT_FDCWD. for libstdc++-v3/ChangeLog * acinclude.m4 (GLIBCXX_CHECK_FILESYSTEM_DEPS): Check for openat. * configure, config.h.in: Rebuilt. * src/filesystem/dir-common.h (openat): Use ::openat if _GLIBCXX_HAVE_OPENAT. * src/filesystem/dir.cc (dir_and_pathname): Use dirfd if _GLIBCXX_HAVE_OPENAT. (cherry picked from commit 93070671eae44f24ba822383e17571a39257c637) Diff: --- libstdc++-v3/acinclude.m4 | 12 +++++++ libstdc++-v3/config.h.in | 3 ++ libstdc++-v3/configure | 55 ++++++++++++++++++++++++++++++++ libstdc++-v3/src/filesystem/dir-common.h | 2 +- libstdc++-v3/src/filesystem/dir.cc | 2 +- 5 files changed, 72 insertions(+), 2 deletions(-) diff --git a/libstdc++-v3/acinclude.m4 b/libstdc++-v3/acinclude.m4 index 138bd58d86c..e3cc3a8e867 100644 --- a/libstdc++-v3/acinclude.m4 +++ b/libstdc++-v3/acinclude.m4 @@ -4772,6 +4772,18 @@ dnl if test $glibcxx_cv_dirfd = yes; then AC_DEFINE(HAVE_DIRFD, 1, [Define if dirfd is available in .]) fi +dnl + AC_CACHE_CHECK([for openat], + glibcxx_cv_openat, [dnl + GCC_TRY_COMPILE_OR_LINK( + [#include ], + [int fd = ::openat(AT_FDCWD, "", 0);], + [glibcxx_cv_openat=yes], + [glibcxx_cv_openat=no]) + ]) + if test $glibcxx_cv_openat = yes; then + AC_DEFINE(HAVE_OPENAT, 1, [Define if openat is available in .]) + fi dnl AC_CACHE_CHECK([for unlinkat], glibcxx_cv_unlinkat, [dnl diff --git a/libstdc++-v3/config.h.in b/libstdc++-v3/config.h.in index f30a8c51c45..2a3972eef54 100644 --- a/libstdc++-v3/config.h.in +++ b/libstdc++-v3/config.h.in @@ -292,6 +292,9 @@ /* Define if defines obsolete isnan function. */ #undef HAVE_OBSOLETE_ISNAN +/* Define if openat is available in . */ +#undef HAVE_OPENAT + /* Define if poll is available in . */ #undef HAVE_POLL diff --git a/libstdc++-v3/configure b/libstdc++-v3/configure index 9b94fd71e42..eac60392121 100755 --- a/libstdc++-v3/configure +++ b/libstdc++-v3/configure @@ -77177,6 +77177,61 @@ $as_echo "$glibcxx_cv_dirfd" >&6; } $as_echo "#define HAVE_DIRFD 1" >>confdefs.h + fi + { $as_echo "$as_me:${as_lineno-$LINENO}: checking for openat" >&5 +$as_echo_n "checking for openat... " >&6; } +if ${glibcxx_cv_openat+:} false; then : + $as_echo_n "(cached) " >&6 +else + if test x$gcc_no_link = xyes; then + cat confdefs.h - <<_ACEOF >conftest.$ac_ext +/* end confdefs.h. */ +#include +int +main () +{ +int fd = ::openat(AT_FDCWD, "", 0); + ; + return 0; +} +_ACEOF +if ac_fn_cxx_try_compile "$LINENO"; then : + glibcxx_cv_openat=yes +else + glibcxx_cv_openat=no +fi +rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext +else + if test x$gcc_no_link = xyes; then + as_fn_error $? "Link tests are not allowed after GCC_NO_EXECUTABLES." "$LINENO" 5 +fi +cat confdefs.h - <<_ACEOF >conftest.$ac_ext +/* end confdefs.h. */ +#include +int +main () +{ +int fd = ::openat(AT_FDCWD, "", 0); + ; + return 0; +} +_ACEOF +if ac_fn_cxx_try_link "$LINENO"; then : + glibcxx_cv_openat=yes +else + glibcxx_cv_openat=no +fi +rm -f core conftest.err conftest.$ac_objext \ + conftest$ac_exeext conftest.$ac_ext +fi + +fi +{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $glibcxx_cv_openat" >&5 +$as_echo "$glibcxx_cv_openat" >&6; } + if test $glibcxx_cv_openat = yes; then + +$as_echo "#define HAVE_OPENAT 1" >>confdefs.h + fi { $as_echo "$as_me:${as_lineno-$LINENO}: checking for unlinkat" >&5 $as_echo_n "checking for unlinkat... " >&6; } diff --git a/libstdc++-v3/src/filesystem/dir-common.h b/libstdc++-v3/src/filesystem/dir-common.h index 365fd527f4d..669780ea23f 100644 --- a/libstdc++-v3/src/filesystem/dir-common.h +++ b/libstdc++-v3/src/filesystem/dir-common.h @@ -199,7 +199,7 @@ struct _Dir_base #endif -#ifdef AT_FDCWD +#if _GLIBCXX_HAVE_OPENAT && defined AT_FDCWD fd = ::openat(fd, pathname, flags); #else // If we cannot use openat, there's no benefit to using posix::open unless diff --git a/libstdc++-v3/src/filesystem/dir.cc b/libstdc++-v3/src/filesystem/dir.cc index b451902c4a1..e64489162e5 100644 --- a/libstdc++-v3/src/filesystem/dir.cc +++ b/libstdc++-v3/src/filesystem/dir.cc @@ -120,7 +120,7 @@ struct fs::_Dir : std::filesystem::_Dir_base dir_and_pathname() const noexcept { const fs::path& p = entry.path(); -#if _GLIBCXX_HAVE_DIRFD +#if _GLIBCXX_HAVE_DIRFD && _GLIBCXX_HAVE_OPENAT return {::dirfd(this->dirp), std::prev(p.end())->c_str()}; #endif return {this->fdcwd(), p.c_str()};