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git-svn-id: svn://svn.valgrind.org/valgrind/trunk@4491 a5019735-40e9-0310-863c-91ae7b9d1cf9
diff --git a/memcheck/mac_replace_strmem.c b/memcheck/mac_replace_strmem.c
index d4e6a83..87f313a 100644
--- a/memcheck/mac_replace_strmem.c
+++ b/memcheck/mac_replace_strmem.c
@@ -227,6 +227,10 @@
STRNLEN(m_libc_so_6, strnlen)
+// Note that this replacement often doesn't get used because gcc inlines
+// calls to strlen() with its own built-in version. This can be very
+// confusing if you aren't expecting it. Other small functions in this file
+// may also be inline by gcc.
#define STRLEN(soname, fnname) \
SizeT VG_REPLACE_FUNCTION(soname,fnname)( const char* str ); \
SizeT VG_REPLACE_FUNCTION(soname,fnname)( const char* str ) \