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()};