Allow multiversioning declarations to match when the actual formal
linkage matches, not just when the storage class is identical.
Additionally, change the ambiguous 'linkage' mismatch to be more
specific and say 'language linkage'.
Given the following case:
```
auto k() {
return undef();
return 1;
}
```
Prior to the patch, clang emits an `cannot initialize return object of type
'auto' with an rvalue of type 'int'` diagnostic on the second return
(because the return type of the function cannot be deduced from the first contain-errors return).
This patch suppresses this error.
Differential Revision: https://reviews.llvm.org/D92211
There were a few issues previously with the target
attribute diagnostics implementation that lead to the
attribute being added to the AST despite having an error
in it.
This patch changes that, and adds a test to ensure it
does not get added to the AST.
Differential Revision: https://reviews.llvm.org/D43359
llvm-svn: 325364
We were trying to emit a diag::err_bad_multiversion_option diagnostic,
which expects an int as its first argument, with a string argument. As
it happens, the string `Feature` that was causing this was shadowing an
int `Feature` from the surrounding scope. :)
llvm-svn: 322530
GCC's attribute 'target', in addition to being an optimization hint,
also allows function multiversioning. We currently have the former
implemented, this is the latter's implementation.
This works by enabling functions with the same name/signature to coexist,
so that they can all be emitted. Multiversion state is stored in the
FunctionDecl itself, and SemaDecl manages the definitions.
Note that it ends up having to permit redefinition of functions so
that they can all be emitted. Additionally, all versions of the function
must be emitted, so this also manages that.
Note that this includes some additional rules that GCC does not, since
defining something as a MultiVersion function after a usage has been made illegal.
The only 'history rewriting' that happens is if a function is emitted before
it has been converted to a multiversion'ed function, at which point its name
needs to be changed.
Function templates and virtual functions are NOT yet supported (not supported
in GCC either).
Additionally, constructors/destructors are disallowed, but the former is
planned.
llvm-svn: 322028
Erich Keane