Debug information was getting confused because input_location was different depending on whether we had looked ahead to see if the next tokens look like a template argument list.
I tried resetting input_location in cp_lexer_rollback_tokens itself, but that caused regressions, so let's just do it here for now. Tested x86_64-pc-linux-gnu, applying to trunk. PR c++/104025 gcc/cp/ChangeLog: * parser.cc (saved_token_sentinel::rollback): Call cp_lexer_set_source_position. (~saved_token_sentinel): Call rollback. gcc/testsuite/ChangeLog: * g++.dg/warn/pr104025.C: New test. Co-authored-by: Jakub Jelinek <ja...@redhat.com> --- gcc/cp/parser.cc | 3 ++- gcc/testsuite/g++.dg/warn/pr104025.C | 20 ++++++++++++++++++++ 2 files changed, 22 insertions(+), 1 deletion(-) create mode 100644 gcc/testsuite/g++.dg/warn/pr104025.C diff --git a/gcc/cp/parser.cc b/gcc/cp/parser.cc index b262b765a9a..60d9f7bb723 100644 --- a/gcc/cp/parser.cc +++ b/gcc/cp/parser.cc @@ -1308,6 +1308,7 @@ struct saved_token_sentinel void rollback () { cp_lexer_rollback_tokens (lexer); + cp_lexer_set_source_position (lexer); mode = STS_DONOTHING; } ~saved_token_sentinel () @@ -1315,7 +1316,7 @@ struct saved_token_sentinel if (mode == STS_COMMIT) cp_lexer_commit_tokens (lexer); else if (mode == STS_ROLLBACK) - cp_lexer_rollback_tokens (lexer); + rollback (); gcc_assert (lexer->saved_tokens.length () == len); } diff --git a/gcc/testsuite/g++.dg/warn/pr104025.C b/gcc/testsuite/g++.dg/warn/pr104025.C new file mode 100644 index 00000000000..9457c8ef52c --- /dev/null +++ b/gcc/testsuite/g++.dg/warn/pr104025.C @@ -0,0 +1,20 @@ +// PR c++/104025 +// { dg-do compile } +// { dg-options "-Wmissing-template-keyword -fcompare-debug" } + +void bar (int); + +struct S { int i; }; + +template <class C> +struct T +{ + int m; + C c; + void foo () + { + bar (c.i < m); + } +}; + +template void T<S>::foo (); base-commit: 7ca21601704c4a637f3cefa7c8814920782354d8 -- 2.27.0