Merge function types in C.
Among other differences, GCC accepts
typedef int IA[];
typedef int A10[10];
static A10 *f(void);
static IA *f(void);
void g(void) {
(void)sizeof(*f());
}
but clang used to reject it with:
invalid application of 'sizeof' to an incomplete type 'IA' (aka 'int []')
The intention of c99's 6.2.7 seems to be that we should use the composite type
and accept as gcc does.
Doing the type merging required some extra fixes:
* Use the type from the function type in initializations, even if an parameter
is available.
* Fix the merging of the noreturn attribute in function types.
* Make CodeGen handle the fact that an parameter type can be different from
the corresponding type in the function type.
llvm-svn: 168895
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index eb75329..001a6ac 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -2402,6 +2402,12 @@
if (getLangOpts().CPlusPlus)
return MergeCXXFunctionDecl(New, Old, S);
+ // Merge the function types so the we get the composite types for the return
+ // and argument types.
+ QualType Merged = Context.mergeTypes(Old->getType(), New->getType());
+ if (!Merged.isNull())
+ New->setType(Merged);
+
return false;
}