As a follow-up to D95691, add new diagnostic groups named
pre-c++N-compat to replace the old diagnostic groups with the standards
listed out explicitly. The old group names are retained for backwards
compatibility.
It's very easy for anonymous external linkage to propagate in C++ through
return types and parameter types. Likewise, it's possible that a template
containing an inline function is only used with parameters that have internal
linkage. Actually diagnosing where the internal linkage comes from is fairly
difficult (both to locate and then to print nicely). Finally, since we only
have one translation unit available, we can't even prove that any of this
violates the ODR.
This warning needs better-defined behavior in C++ before it can really go in.
Rewording of the C warning (which /is/ specified by C99) coming shortly.
llvm-svn: 158836
Per post-commit review, it's not appropriate to use ExtWarn in C++, because
we can't prove that the inline function will actually be defined in more than
one place (and thus we can't prove that this violates the ODR).
This removes the warning entirely from uses in the main source file in C++.
llvm-svn: 158689
This includes treating anonymous namespaces like internal linkage, and allowing
const variables to be used even if internal. The whole thing's been broken out
into a separate function to avoid nested ifs.
llvm-svn: 158683
- 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
Fangrui Song