A significant number of our tests in C accidentally use functions
without prototypes. This patch converts the function signatures to have
a prototype for the situations where the test is not specific to K&R C
declarations. e.g.,
void func();
becomes
void func(void);
This is the third batch of tests being updated (there are a significant
number of other tests left to be updated).
Sema::MergeFunctionDecl attempts merging two decls even if the old decl
is invalid. This can lead to interesting circumstances where we
successfully merge the decls but the result makes no sense.
Take the following for example:
template <typename T>
int main(void);
int main(void);
Sema will not consider these to be overloads of the same name because
main can't be overloaded, which means that this must be a redeclaration.
In this case the templated decl is compatible with the non-templated
decl allowing the Sema::CheckFunctionDeclaration machinery to move on
and do bizarre things like setting the previous decl of a non-templated
decl to a templated decl!
The way I see it, we should just bail from MergeFunctionDecl if the old
decl is invalid.
This fixes PR16531.
llvm-svn: 185779