c: remaining fix for the composite type inconsistency [PR120510]HEADtrunkmaster

There is an old GNU extension which allows overriding the
promoted old-style arguments when there is an earlier prototype
An example (from a test added for PR16666) is the following.

float dremf (float, float);

float
dremf (x, y)
     float x, y;
{
  return x + y;
}

The types of the two declarations are not compatible, because
the arguments are not self-promoting.  Add a special case
to function_types_compatible_p that can be toggled via a flag
for comptypes_internal and add a helper function to be able to
add the checking assertions to composite_type.

	PR c/120510

gcc/c/ChangeLog:
	* c-typeck.cc (composite_type_internal): Activate checking
	assertions for all types and also inputs.
	(comptypes_for_composite_check): New helper function.
	(function_types_compatible_p): Add exception.

gcc/testsuite/ChangeLog:
	* gcc.dg/old-style-prom-4.c: New test.

0 files changed, 0 insertions, 0 deletions