From 3e9c52250a3ab6664c53ea6b3923acfbe8e09e4e Mon Sep 17 00:00:00 2001 From: Davi Arnaut Date: Wed, 20 Oct 2010 16:21:40 -0200 Subject: Bug#45288: pb2 returns a lot of compilation warnings Fix assorted warnings that are generated in optimized builds. Most of it is silencing variables that are set but unused. This patch also introduces the MY_ASSERT_UNREACHABLE macro which helps the compiler to deduce that a certain piece of code is unreachable. include/my_compiler.h: Use GCC's __builtin_unreachable if available. It allows GCC to deduce the unreachability of certain code paths, thus avoiding warnings that, for example, accused that a variable could be used without being initialized (due to unreachable code paths). --- include/my_compiler.h | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/my_compiler.h b/include/my_compiler.h index 1cd46ff4260..c7d334999d0 100644 --- a/include/my_compiler.h +++ b/include/my_compiler.h @@ -32,8 +32,15 @@ /* GNU C/C++ */ #if defined __GNUC__ +/* Convenience macro to test the minimum required GCC version. */ +# define MY_GNUC_PREREQ(maj, min) \ + ((__GNUC__ << 16) + __GNUC_MINOR__ >= ((maj) << 16) + (min)) /* Any after 2.95... */ # define MY_ALIGN_EXT +/* Comunicate to the compiler the unreachability of the code. */ +# if MY_GNUC_PREREQ(4,5) +# define MY_ASSERT_UNREACHABLE() __builtin_unreachable() +# endif /* Microsoft Visual C++ */ #elif defined _MSC_VER @@ -67,7 +74,7 @@ #endif /** - Generic compiler-dependent features. + Generic (compiler-independent) features. */ #ifndef MY_ALIGNOF # ifdef __cplusplus @@ -79,6 +86,10 @@ # endif #endif +#ifndef MY_ASSERT_UNREACHABLE +# define MY_ASSERT_UNREACHABLE() do { assert(0); } while (0) +#endif + /** C++ Type Traits */ -- cgit v1.2.1