X-Git-Url: https://ruderich.org/simon/gitweb/?p=coloredstderr%2Fcoloredstderr.git;a=blobdiff_plain;f=src%2Fcompiler.h;h=304521e03c5220752a354629345c772b7fc761d4;hp=85b58b1d90dc86e9f002c36099d156148cec50f6;hb=8a65b4486febf00e3fad5bafc3773a811e675a4c;hpb=1068648718dad86471451266fcdf4248bb79f3fe

diff --git a/src/compiler.h b/src/compiler.h
index 85b58b1..304521e 100644
--- a/src/compiler.h
+++ b/src/compiler.h
@@ -1,7 +1,7 @@
 /*
  * Compiler specific macros.
  *
- * Copyright (C) 2013  Simon Ruderich
+ * Copyright (C) 2013-2015  Simon Ruderich
  *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -26,10 +26,19 @@
 # define always_inline __attribute__((always_inline))
 /* Unused parameter. */
 # define unused        __attribute__((unused))
+/* Mark the function protected, which means it can't be overwritten by other
+ * modules (libraries), e.g. with LD_PRELOAD); otherwise same as the default
+ * visibility. This causes the compiler not use the PLT (and no relocations)
+ * for local calls from inside this module; but the symbols are still
+ * exported. This is faster and in this case prevents useless lookups as we
+ * hook those functions and nobody else should modify them. Not strictly
+ * necessary, but nice to have. */
+# define visibility_protected __attribute__((visibility("protected")))
 #else
 # define noinline
 # define always_inline
 # define unused
+# define visibility_protected
 #endif
 
 /* Branch prediction information for the compiler. */