https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106955
Bug ID: 106955 Summary: [13 Regression] '-fcompare-debug' failure w/ -std=c++20 -O1 -ftree-parallelize-loops=2 -fno-ipa-sra --param ggc-min-expand=55 Product: gcc Version: 13.0 Status: UNCONFIRMED Keywords: compare-debug-failure Severity: normal Priority: P3 Component: debug Assignee: unassigned at gcc dot gnu.org Reporter: asolokha at gmx dot com Target Milestone: --- Created attachment 53582 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=53582&action=edit gkd diff g++ 13.0.0 20220911 snapshot (g:0ea5e3f4542832b8da016b152695e64a2a386309) fails -fcompare-debug check when compiling the following testcase, reduced from test/std/containers/sequences/forwardlist/forwardlist.ops/sort.pass.cpp from the libc++ 14.0.6 test suite, w/ -std=c++20 -O1 -ftree-parallelize-loops=2 -fno-ipa-sra --param ggc-min-expand=55: #include <forward_list> #include <iterator> #include <algorithm> #include <vector> void test_stable () { std::vector<int> v; for (int i = 0; i < 1000; ++i) v.push_back (i); for (int i = 0; i < 1000; ++i) v[i] = i; } % g++-13.0.0 -std=c++20 -O1 -fcompare-debug -ftree-parallelize-loops=2 -fno-ipa-sra --param ggc-min-expand=55 -c dfptqjrz.cpp g++-13.0.0: error: dfptqjrz.cpp: '-fcompare-debug' failure gkd diff attached. Preprocessed testcase is still being reduced, currently at 06:43:08 INFO (66.7%, 468334 bytes, 7781 lines) I'll post it here once the reducer yields something meaningful under several kilobytes in size.