Represent pass_object_size attrs in ExtParameterInfo
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
diff --git a/clang/test/Modules/Inputs/overloadable-attrs/a.h b/clang/test/Modules/Inputs/overloadable-attrs/a.h
index e7dabfb..1af769d 100644
--- a/clang/test/Modules/Inputs/overloadable-attrs/a.h
+++ b/clang/test/Modules/Inputs/overloadable-attrs/a.h
@@ -14,3 +14,15 @@
constexpr int fn5(int i) __attribute__((enable_if(i, ""))) { return 1; }
constexpr int fn5(int i) { return 0; }
}
+
+namespace pass_object_size_attrs {
+constexpr int fn1(void *const a __attribute__((pass_object_size(0)))) {
+ return 1;
+}
+constexpr int fn1(void *const a) { return 0; }
+
+constexpr int fn2(void *const a) { return 0; }
+constexpr int fn2(void *const a __attribute__((pass_object_size(0)))) {
+ return 1;
+}
+}