From: Adhemerval Zanella Date: Tue, 10 Sep 2024 12:22:19 +0000 (-0300) Subject: Disable _TIME_BITS if the compiler defaults to it X-Git-Url: https://sourceware.org/git/?a=commitdiff_plain;h=4d8965f1304a205f7580fe23bb2d462828d1f8e5;p=glibc.git Disable _TIME_BITS if the compiler defaults to it Even though building glibc with 64 bit time_t flags is not supported, and the usual way is to patch the build system to avoid it; some systems do enable it by default, and it increases the requirements to build glibc in such cases (it also does not help newcomers when trying to build glibc). The conform namespace and linknamespace tests also do not expect that flag to be set by default, so disable it as well. Checked with a build/check for major ABI and some (i386, arm, mipsel, hppa) with a toolchain that has LFS flags by default. Reviewed-by: DJ Delorie --- diff --git a/Makeconfig b/Makeconfig index c0c89e6685..a0abc2239b 100644 --- a/Makeconfig +++ b/Makeconfig @@ -1014,6 +1014,9 @@ endif # Filter out LFS flags if compiler defines it by default. +cflags += $(no-file-offset-bits-source) +# Filter out 64 bit time_t flags if compiler defines it by default. ++cflags += $(no-time-bits-source) + # Each sysdeps directory can contain header files that both will be # used to compile and will be installed. Each can also contain an # include/ subdirectory, whose header files will be used to compile diff --git a/configure b/configure index 5b9cc51067..9c0c0dce03 100755 --- a/configure +++ b/configure @@ -635,6 +635,7 @@ libc_cv_gcc_unwind_find_fde libc_extra_cppflags libc_extra_cflags libc_cv_cxx_thread_local +no_time_bits_source no_file_offset_bits_source fortify_source no_fortify_source @@ -7815,6 +7816,35 @@ fi config_vars="$config_vars no-file-offset-bits-source = $no_file_offset_bits_source" +cat confdefs.h - <<_ACEOF >conftest.$ac_ext +/* end confdefs.h. */ + +int +main (void) +{ + +#ifndef _TIME_BITS +# error _TIME_BITS not defined +#endif + ; + return 0; +} +_ACEOF +if ac_fn_c_try_cpp "$LINENO" +then : + libc_cv_compiler_default_time_bits=yes +else case e in #( + e) libc_cv_compiler_default_time_bits=no ;; +esac +fi +rm -f conftest.err conftest.i conftest.$ac_ext +if test "$libc_cv_compiler_default_time_bits" = yes +then : + no_time_bits_source="-U_TIME_BITS" +fi + +config_vars="$config_vars +no-time-bits-source = $no_time_bits_source" { printf "%s\n" "$as_me:${as_lineno-$LINENO}: checking whether the assembler requires one version per symbol" >&5 printf %s "checking whether the assembler requires one version per symbol... " >&6; } diff --git a/configure.ac b/configure.ac index 160c863416..d5a00461ff 100644 --- a/configure.ac +++ b/configure.ac @@ -1576,6 +1576,17 @@ AS_IF([test "$libc_cv_compiler_default_file_offset_bits" = yes], AC_SUBST(no_file_offset_bits_source) LIBC_CONFIG_VAR([no-file-offset-bits-source], [$no_file_offset_bits_source]) +dnl Check if compiler define _TIME_BITS by default +AC_PREPROC_IFELSE([AC_LANG_PROGRAM([[]], [[ +#ifndef _TIME_BITS +# error _TIME_BITS not defined +#endif]])], + [libc_cv_compiler_default_time_bits=yes], + [libc_cv_compiler_default_time_bits=no]) +AS_IF([test "$libc_cv_compiler_default_time_bits" = yes], + [no_time_bits_source="-U_TIME_BITS"]) +AC_SUBST(no_time_bits_source) +LIBC_CONFIG_VAR([no-time-bits-source], [$no_time_bits_source]) dnl Starting with binutils 2.35, GAS can attach multiple symbol versions dnl to one symbol (PR 23840). diff --git a/conform/Makefile b/conform/Makefile index 50293a195b..57a1f5b546 100644 --- a/conform/Makefile +++ b/conform/Makefile @@ -372,7 +372,7 @@ test-xfail-UNIX98/ndbm.h/conform = yes test-xfail-XOPEN2K/ndbm.h/conform = yes test-xfail-XOPEN2K8/ndbm.h/conform = yes -conformtest-cc-flags = -I../include $(+sysdep-includes) $(sysincludes) -I.. $(no-file-offset-bits-source) +conformtest-cc-flags = -I../include $(+sysdep-includes) $(sysincludes) -I.. $(no-file-offset-bits-source) $(no-time-bits-source) # conformtest-xfail-conds may be set by a sysdeps Makefile fragment to # a list of conditions that are considered to be true when encountered # in xfail[cond]- lines in test expectations.