c++: Don't call fold from cp_fold if one of the operands is an error_mark [PR118525]

While adding a new match pattern, g++.dg/cpp2a/consteval36.C started to ICE and that was
because we would call fold even if one of the operands of the comparison was an error_mark_node.
I found a new testcase which also ICEs before this patch too so show the issue was latent.

So there is code in cp_fold to avoid calling fold when one of the operands become error_mark_node
but with the addition of consteval, the replacement of an invalid call is replaced before the call
to cp_fold and there is no way to pop up the error_mark. So this patch changes the current code to
check if the operands of the expression are error_mark_node before checking if the folded operand
is different from the previous one.

Bootstrapped and tested on x86_64-linux-gnu.

	PR c++/118525

gcc/cp/ChangeLog:

	* cp-gimplify.cc (cp_fold): Check operands of unary, binary, cond/vec_cond
	and array_ref for error_mark before checking if the operands had changed.

gcc/testsuite/ChangeLog:

	* g++.dg/cpp2a/consteval38.C: New test.

Signed-off-by: Andrew Pinski <quic_apinski@quicinc.com>

0 files changed, 0 insertions, 0 deletions