mesa: Detect and provide macros for function attributes pure and const.
These are really useful hints to the compiler in the absence of link-time
optimization, and I'm going to use them in VC4.
I've made the const attribute be ATTRIBUTE_CONST unlike other function
attributes, because we have other things in the tree #defining CONST for
their own unrelated purposes.
v2: Alphabetize.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org> (v1)
diff --git a/configure.ac b/configure.ac
index bdfd134..bb6d4f6 100644
--- a/configure.ac
+++ b/configure.ac
@@ -205,10 +205,12 @@
AX_GCC_BUILTIN([__builtin_popcountll])
AX_GCC_BUILTIN([__builtin_unreachable])
+AX_GCC_FUNC_ATTRIBUTE([const])
AX_GCC_FUNC_ATTRIBUTE([flatten])
AX_GCC_FUNC_ATTRIBUTE([format])
AX_GCC_FUNC_ATTRIBUTE([malloc])
AX_GCC_FUNC_ATTRIBUTE([packed])
+AX_GCC_FUNC_ATTRIBUTE([pure])
AX_GCC_FUNC_ATTRIBUTE([unused])
AX_GCC_FUNC_ATTRIBUTE([warn_unused_result])