https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94938
--- Comment #4 from CVS Commits ---
The master branch has been updated by Marek Polacek :
https://gcc.gnu.org/g:1e89178889741c9c4d6a61e5a01c40a8a182fa68
commit r11-155-g1e89178889741c9c4d6a61e5a01c40a8a182fa68
Author: Marek Polacek
Date: Mon May 4 18:34:38 2020 -0400
c++: ICE in value_dependent_expression_p in C++98 mode [PR94938]
Here we ICE with -std=c++98 since the newly added call to
uses_template_parms
(r10-6357): we hit
26530 gcc_assert (cxx_dialect >= cxx11
26531 || INTEGRAL_OR_ENUMERATION_TYPE_P (type));
and TYPE is a record type. The problem is that the argument to
value_dependent_expression_p does not satisfy potential_constant_expression
which it must, as the comment explains. I thought about fixing this in
uses_template_parms -- only call v_d_e_p if p_c_e is true, but in this
case we want to also suppress the warnings if we don't have a constant
expression. I couldn't simply check TREE_CONSTANT as in
compute_array_index_type_loc, because then we'd stop warning in the new
Wtype-limits3.C test.
Fixed by using type_dependent_expression_p_push instead. This means
that we won't suppress the warnings for value-dependent expressions that
aren't type-dependent, e.g. sizeof (T). This only seems to make a
difference for -Wdiv-by-zero, now tested in Wdiv-by-zero-3.C, where I
think it's reasonable to warn. It could make -Wtautological-compare
warn more, but that warning doesn't trigger when it gets constant
arguments.
Wtype-limits4.C is a test reduced from poly-int.h and it tests a scenario
that was missing in our testsuite.
This patch also moves the warning_sentinels after the RECURs -- we mean
to use them for build_x_binary_op purposes only.
PR c++/94938
* pt.c (tsubst_copy_and_build): Call
type_dependent_expression_p_push
instead of uses_template_parms. Move the warning_sentinels after
the
RECURs.
* g++.dg/warn/Wdiv-by-zero-3.C: New test.
* g++.dg/warn/Wtype-limits4.C: New test.
* g++.dg/warn/template-2.C: New test.
* g++.old-deja/g++.pt/crash10.C: Add dg-warning.
