Hi! We are getting a gnuradio PCH ICE /usr/include/pybind11/stl.h:447:1: internal compiler error: in gt_pch_save, at ggc-common.cc:693 0x1304e7d gt_pch_save(_IO_FILE*) ../../gcc/ggc-common.cc:693 0x12a45fb c_common_write_pch() ../../gcc/c-family/c-pch.cc:175 0x18ad711 c_parse_final_cleanups() ../../gcc/cp/decl2.cc:5062 0x213988b c_common_parse_file() ../../gcc/c-family/c-opts.cc:1319 (unfortunately it isn't reproduceable always, but often needs up to 100 attempts, isn't reproduceable in a cross etc.). The bug is in the assertion I've added in gt_pch_save when adding relocation support for the PCH files in case they happen not to be mmapped at the selected address. addr is a relocated address which points to a location in the PCH blob (starting at mmi.preferred_base, with mmi.size bytes) which contains a pointer that needs to be relocated. So the assertion is meant to verify the address is within the PCH blob, obviously it needs to be equal or above mmi.preferred_base, but I got the other comparison wrong and when one is very unlucky and the last sizeof (void *) bytes of the blob happen to be a pointer which needs to be relocated, such as on the s390x host addr 0x8008a04ff8, mmi.preferred_base 0x8000000000 and mmi.size 0x8a05000, addr + sizeof (void *) is equal to mmi.preferred_base + mmi.size and that is still fine, both addresses are end of something.
Bootstrapped/regtested on x86_64-linux and i686-linux, plus tested on s390x on the testcase which was ICEing in 1-100 iterations and there it survived 7750 attempts without ICE (forgot to stop it earlier), ok for trunk? 2024-02-03 Jakub Jelinek <ja...@redhat.com> * ggc-common.cc (gt_pch_save): Allow addr to be equal to mmi.preferred_base + mmi.size - sizeof (void *). --- gcc/ggc-common.cc.jj 2024-01-03 11:51:39.397622018 +0100 +++ gcc/ggc-common.cc 2024-02-02 17:33:13.106727473 +0100 @@ -692,7 +692,7 @@ gt_pch_save (FILE *f) { gcc_assert ((uintptr_t) addr >= (uintptr_t) mmi.preferred_base && ((uintptr_t) addr + sizeof (void *) - < (uintptr_t) mmi.preferred_base + mmi.size)); + <= (uintptr_t) mmi.preferred_base + mmi.size)); if (addr == last_addr) continue; if (last_addr == NULL) Jakub