ASSERT_SRW_WAITBLOCK may evaluate to nothing

target: lib/rtl/srw.c

The patch below casts the ASSERT_SRW_WAITBLOCK macro to void, to prevent a no-effect expansion due to the strict handling of (variadic or not) macros in recent versions of GCC.
Notice that build runs fine with -Wno-unused, but I think this goes against the purposes of -Werror in the build flags (and in fact, GCC 4.3+ break with this warning). This "problem" is nothing critical, but it will avoid future headhaches.

Marcelo A. B. Slomp

Index: lib/rtl/srw.c
===================================================================
— lib/rtl/srw.c (revision 34937)
+++ lib/rtl/srw.c (working copy)
@@ -91,7 +91,8 @@
/* This macro will cause the code to assert if compiled with a buggy
version of GCC that doesn't align the wait blocks properly on the stack! */
#define ASSERT_SRW_WAITBLOCK(ptr) \

• ASSERT(((ULONG_PTR)ptr & ((1 << RTL_SRWLOCK_BITS) - 1)) == 0)
  + (_attribute_((unused))void) \
  + ASSERT(((ULONG_PTR)ptr & ((1 << RTL_SRWLOCK_BITS) - 1)) == 0)
  #else
  #define ASSERT_SRW_WAITBLOCK(ptr)
  #endif