From f0e0e8bd08b4d4e7c89a5a3b7d9a3c083f7e5432 Mon Sep 17 00:00:00 2001 From: Vincent Fazio Date: Wed, 8 Feb 2023 12:58:37 +0000 Subject: [PATCH] Detect symver attribute support On Microblaze, builds will fail when trying to add symver information because __attribute__((symver ..)) is not supported even though __has_attribute(__symver__) returns true. Support for symver needs to be detected via a compile test since __has_attribute can report false positives [0]. Add a configure compile check for __attribute__((symver ..)) to ensure it is supported and define a variable to advertise support. [0] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101766#c1 Upstream: https://github.com/tukaani-project/xz/pull/32 Signed-off-by: Thomas Petazzoni Signed-off-by: Vincent Fazio [Peter: patch configure instead of configure.ac so autoreconf isn't triggered at build time] Signed-off-by: Peter Korsgaard --- configure | 15 +++++++++++++++ src/liblzma/common/common.h | 2 +- 2 files changed, 16 insertions(+), 1 deletion(-) diff --git a/src/liblzma/common/common.h b/src/liblzma/common/common.h index 671d3bc..27b56ee 100644 --- a/src/liblzma/common/common.h +++ b/src/liblzma/common/common.h @@ -76,7 +76,7 @@ // too (which doesn't support __symver__) so use it to detect if __symver__ // is available. This should be far more reliable than looking at compiler // version macros as nowadays especially __GNUC__ is defined by many compilers. -# if lzma_has_attribute(__symver__) +# if defined(HAVE_SYMVER_ATTRIBUTE) # define LZMA_SYMVER_API(extnamever, type, intname) \ extern __attribute__((__symver__(extnamever))) \ LZMA_API(type) intname diff --git a/configure b/configure index ff0eed5..e685b30 100755 --- a/configure +++ b/configure @@ -16687,6 +16687,21 @@ printf "%s\n" "" >&6; } printf "%s\n" "#define HAVE_SYMBOL_VERSIONS_LINUX $have_symbol_versions_linux" >>confdefs.h + OLD_CFLAGS="$CFLAGS" + CFLAGS="$CFLAGS -Werror" # we need -Werror to make sure the attribute is not ignored + cat confdefs.h - <<_ACEOF >conftest.$ac_ext +/* end confdefs.h. */ +__attribute__ ((symver ("test@TEST"))) void foo(void) { } + +_ACEOF +if ac_fn_c_try_compile "$LINENO" +then : + +printf "%s\n" "#define HAVE_SYMVER_ATTRIBUTE 1" >>confdefs.h + +fi +rm -f core conftest.err conftest.$ac_objext conftest.beam conftest.$ac_ext + CFLAGS="$OLD_CFLAGS" ;; *) enable_symbol_versions=generic -- 2.34.1