https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107461
--- Comment #14 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The releases/gcc-12 branch has been updated by Patrick Palka <ppa...@gcc.gnu.org>: https://gcc.gnu.org/g:eda24f6c12b6d3777ff3bf3656187e695a3e8dc2 commit r12-9110-geda24f6c12b6d3777ff3bf3656187e695a3e8dc2 Author: Patrick Palka <ppa...@redhat.com> Date: Sun Feb 5 21:35:33 2023 -0500 c++: equivalence of non-dependent calls [PR107461] After r13-5684-g59e0376f607805 the (pruned) callee of a non-dependent CALL_EXPR is a bare FUNCTION_DECL rather than ADDR_EXPR of FUNCTION_DECL. This innocent change revealed that cp_tree_equal doesn't first check dependence of a CALL_EXPR before treating a FUNCTION_DECL callee as a dependent name, which leads to us incorrectly accepting the first two testcases below and rejecting the third: * In the first testcase, cp_tree_equal incorrectly returns true for the two non-dependent CALL_EXPRs f(0) and f(0) (whose CALL_EXPR_FN are different FUNCTION_DECLs) which causes us to treat #2 as a redeclaration of #1. * Same issue in the second testcase, for f<int*>() and f<char>(). * In the third testcase, cp_tree_equal incorrectly returns true for f<int>() and f<void(*)(int)>() which causes us to conflate the two dependent specializations A<decltype(f<int>()(U()))> and A<decltype(f<void(*)(int)>()(U()))>. This patch fixes this by making called_fns_equal treat two callees as dependent names only if the overall CALL_EXPRs are dependent, via a new convenience function call_expr_dependent_name that is like dependent_name but also checks dependence of the overall CALL_EXPR. PR c++/107461 gcc/cp/ChangeLog: * cp-tree.h (call_expr_dependent_name): Declare. * pt.cc (iterative_hash_template_arg) <case CALL_EXPR>: Use call_expr_dependent_name instead of dependent_name. * tree.cc (call_expr_dependent_name): Define. (called_fns_equal): Adjust to take two CALL_EXPRs instead of CALL_EXPR_FNs thereof. Use call_expr_dependent_name instead of dependent_name. (cp_tree_equal) <case CALL_EXPR>: Adjust call to called_fns_equal. gcc/testsuite/ChangeLog: * g++.dg/cpp0x/overload5.C: New test. * g++.dg/cpp0x/overload5a.C: New test. * g++.dg/cpp0x/overload6.C: New test. (cherry picked from commit 31924665c86d47af6b1f22a74f594f2e1dc0ed2d)
