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-rw-r--r--src/liblzma/check/crc_common.h25
1 files changed, 25 insertions, 0 deletions
diff --git a/src/liblzma/check/crc_common.h b/src/liblzma/check/crc_common.h
index 856665db..5a86556f 100644
--- a/src/liblzma/check/crc_common.h
+++ b/src/liblzma/check/crc_common.h
@@ -128,6 +128,31 @@
# endif
#endif
+#ifdef CRC_USE_IFUNC
+// Two function attributes are needed to make IFUNC safe with GCC.
+//
+// no-omit-frame-pointer prevents false Valgrind issues when combined with
+// a few other compiler flags. The optimize attribute is supported on
+// GCC >= 4.4 and is not supported with Clang.
+# if TUKLIB_GNUC_REQ(4,4) && !defined(__clang__)
+# define no_omit_frame_pointer \
+ __attribute__((optimize("no-omit-frame-pointer")))
+# else
+# define no_omit_frame_pointer
+# endif
+
+// The __no_profile_instrument_function__ attribute support is checked when
+// determining if ifunc can be used, so it is safe to use unconditionally.
+// This attribute is needed because GCC can add profiling to the IFUNC
+// resolver, which calls functions that have not yet been relocated leading
+// to a crash on liblzma start up.
+# define lzma_resolver_attributes \
+ __attribute__((__no_profile_instrument_function__)) \
+ no_omit_frame_pointer
+#else
+# define lzma_resolver_attributes
+#endif
+
// For CRC32 use the generic slice-by-eight implementation if no optimized
// version is available.
#if !defined(CRC32_ARCH_OPTIMIZED) && !defined(CRC32_GENERIC)