The goal of this is to fix a bug in modules where we'd merge
FunctionDecls that differed in their pass_object_size attributes. Since
we can overload on the presence of pass_object_size attributes, this
behavior is incorrect.
We don't represent `N` in `pass_object_size(N)` as part of
ExtParameterInfo, since it's an error to overload solely on the value of
N. This means that we have a bug if we have two modules that declare
functions that differ only in their pass_object_size attrs, like so:
// In module A, from a.h
void foo(char *__attribute__((pass_object_size(0))));
// In module B, from b.h
void foo(char *__attribute__((pass_object_size(1))));
// In module C, in main.c
#include "a.h"
#include "b.h"
At the moment, we'll merge the foo decls, when we should instead emit a
diagnostic about an invalid overload. We seem to have similar (silent)
behavior if we overload only on the return type of `foo` instead; I'll
try to find a good place to put a FIXME (or I'll just file a bug) soon.
This patch also fixes a bug where we'd not output the proper extended
parameter info for declarations with pass_object_size attrs.
llvm-svn: 296076
Two functions that differ only in their enable_if attributes are
considered overloads, so we should check for those when we're trying to
figure out if two functions are mergeable.
We need to do the same thing for pass_object_size, as well. Looks like
that'll be a bit less trivial, since we sometimes do these merging
checks before we have pass_object_size attributes available (see the
merge checks in ASTDeclReader::VisitFunctionDecl that happen before we
read parameters, and merge checks in calls to ReadDeclAs<>()).
llvm-svn: 295252
George Burgess IV