GCC has always supported this on PowerPC and 4.8 supports it on all platforms,
so it's a good idea to expose it in clang too. LLVM supports this on all targets.
llvm-svn: 165362
- This is designed to make it obvious that %clang_cc1 is a "test variable"
which is substituted. It is '%clang_cc1' instead of '%clang -cc1' because it
can be useful to redefine what gets run as 'clang -cc1' (for example, to set
a default target).
llvm-svn: 91446
scheme to be more useful.
The new scheme introduces a set of categories that should be more
readable, and also reflects what we want to consider as an extension
more accurately. Specifically, it makes the "what is a keyword"
determination accurately reflect whether the keyword is a GNU or
Microsoft extension.
I also introduced separate flags for keyword aliases; this is useful
because the classification of the aliases is mostly unrelated to the
classification of the original keyword.
This patch treats anything that's in the implementation
namespace (prefixed with "__", or "_X" where "X" is any upper-case
letter) as a keyword without marking it as an extension. This is
consistent with the standards in that an implementation is allowed to define
arbitrary extensions in the implementation namespace without violating
the standard. This gets rid of all the nasty "extension used" warnings
for stuff like __attribute__ in -pedantic mode. We still warn for
extensions outside of the the implementation namespace, like typeof.
If someone wants to implement -Wextensions or something like that, we
could add additional information to the keyword table.
This also removes processing for the unused "Boolean" language option;
such an extension isn't supported on any other C implementation, so I
don't see any point to adding it.
The changes to test/CodeGen/inline.c are required because previously, we
weren't actually disabling the "inline" keyword in -std=c89 mode.
I'll remove Boolean and NoExtensions from LangOptions in a follow-up
commit.
llvm-svn: 70281
condition as a constant even if the unevaluated side is a not a constant.
We don't do this when extensions are off, and we emit a warning when this
happens:
t.c:22:11: warning: expression is not a constant, but is accepted as one by GNU extensions
short t = __builtin_constant_p(5353) ? 42 : somefunc();
^ ~~~~~~~~~~
suggestions for improvement are welcome. This is obviously horrible, but
is required for real-world code.
llvm-svn: 57153
- Enabled for builtins which are always constant expressions
(__builtin_huge_val*, __builtin_inf*, __builtin_constant_p,
__builtin_classify_type, __builtin___CFStringMakeConstantString).
Added Builtin::Context::isConstantExpr.
- Currently overly simply interface which only works for builtins
whose constantexprness does not depend on their arguments.
CallExpr::isBuiltinConstantExpr now takes an ASTContext argument.
llvm-svn: 56983
Andy Gibbs