From 291553a0132936611d48f41e924601dff8941537 Mon Sep 17 00:00:00 2001 From: John Spencer maillist-alsa@barfooze.de Date: Sat, 15 Nov 2014 13:41:00 +0100 Subject: [PATCH] snd_dlsym: only do versioning checks if built --with-versioning
a combination of some of the following garbage collecting LD/CFLAGS -Os -g0 -fdata-sections -ffunction-sections -s -Wl,--gc-sections -fno-unwind-tables -fno-asynchronous-unwind-tables causes the symbol versioning marker symbols to be removed from BSS since they're otherwise unreferenced. this causes dlsym failing to find them which results in runtime breakage:
$ alsamixer ALSA lib dlmisc.c:142:(snd_dlsym_verify) unable to verify version for symbol snd_config_hook_load ALSA lib conf.c:3328:(snd_config_hooks_call) symbol snd_config_hook_load is not defined inside (null) ALSA lib conf.c:3788:(snd_config_update_r) hooks failed, removing configuration cannot open mixer: No such device or address
correct DSO: $ objdump -T libasound.so.2.strip | grep _snd_config_hook_load_dlsym_config_hook_001 001196bc g DO .bss 00000001 _snd_config_hook_load_dlsym_config_hook_001
incorrect DSO: $ objdump -T libs/libasound.so.2 | grep _snd_config_hook_load_dlsym_config_hook_001 00000000 g DO *ABS* 00000001 _snd_config_hook_load_dlsym_config_hook_001
since alsa was built with --without-versioning, doing those versioning checks at all is unnecessary and harmful and thus now disabled in this case.
Signed-off-by: John Spencer maillist-alsa@barfooze.de
--- src/dlmisc.c | 2 ++ 1 file changed, 2 insertions(+)
From 291553a0132936611d48f41e924601dff8941537 Mon Sep 17 00:00:00 2001 From: John Spencer maillist-alsa@barfooze.de Date: Sat, 15 Nov 2014 13:41:00 +0100 Subject: [PATCH] snd_dlsym: only do versioning checks if built --with-versioning
a combination of some of the following garbage collecting LD/CFLAGS -Os -g0 -fdata-sections -ffunction-sections -s -Wl,--gc-sections -fno-unwind-tables -fno-asynchronous-unwind-tables causes the symbol versioning marker symbols to be removed from BSS since they're otherwise unreferenced. this causes dlsym failing to find them which results in runtime breakage:
$ alsamixer ALSA lib dlmisc.c:142:(snd_dlsym_verify) unable to verify version for symbol snd_config_hook_load ALSA lib conf.c:3328:(snd_config_hooks_call) symbol snd_config_hook_load is not defined inside (null) ALSA lib conf.c:3788:(snd_config_update_r) hooks failed, removing configuration cannot open mixer: No such device or address
correct DSO: $ objdump -T libasound.so.2.strip | grep _snd_config_hook_load_dlsym_config_hook_001 001196bc g DO .bss 00000001 _snd_config_hook_load_dlsym_config_hook_001
incorrect DSO: $ objdump -T libs/libasound.so.2 | grep _snd_config_hook_load_dlsym_config_hook_001 00000000 g DO *ABS* 00000001 _snd_config_hook_load_dlsym_config_hook_001
since alsa was built with --without-versioning, doing those versioning checks at all is unnecessary and harmful and thus now disabled in this case.
Signed-off-by: John Spencer maillist-alsa@barfooze.de
--- src/dlmisc.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/src/dlmisc.c b/src/dlmisc.c index 4b8a02c..62f7047 100644 --- a/src/dlmisc.c +++ b/src/dlmisc.c @@ -177,11 +177,13 @@ void *snd_dlsym(void *handle, const char *name, const char *version) } #endif #ifdef HAVE_LIBDL +#ifdef VERSIONED_SYMBOLS if (version) { err = snd_dlsym_verify(handle, name, version); if (err < 0) return NULL; } +#endif return dlsym(handle, name); #else return NULL;