https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117101
--- Comment #3 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Simon Martin <simar...@gcc.gnu.org>: https://gcc.gnu.org/g:5821f5c8c89a054e34cea00e042996dfdcd7e102 commit r15-4958-g5821f5c8c89a054e34cea00e042996dfdcd7e102 Author: Simon Martin <si...@nasilyan.com> Date: Tue Nov 5 10:16:39 2024 +0100 c++: Don't crash upon invalid placement new operator [PR117101] We currently crash upon the following invalid code (notice the "void void**" parameter) === cut here === using size_t = decltype(sizeof(int)); void *operator new(size_t, void void **p) noexcept { return p; } int x; void f() { int y; new (&y) int(x); } === cut here === The problem is that in this case, we end up with a NULL_TREE parameter list for the new operator because of the error, and (1) coerce_new_type wrongly complains about the first parameter type not being size_t, (2) std_placement_new_fn_p blindly accesses the parameter list, hence a crash. This patch does NOT address #1 since we can't easily distinguish between a new operator declaration without parameters from one with erroneous parameters (and it's not worth the risk to refactor and break things for an error recovery issue) hence a dg-bogus in new52.C, but it does address #2 and the ICE by simply checking the first parameter against NULL_TREE. It also adds a new testcase checking that we complain about new operators with no or invalid first parameters, since we did not have any. PR c++/117101 gcc/cp/ChangeLog: * init.cc (std_placement_new_fn_p): Check first_arg against NULL_TREE. gcc/testsuite/ChangeLog: * g++.dg/init/new52.C: New test. * g++.dg/init/new53.C: New test.
