Bootstrapped and regtested on x86_64-pc-linu-xgnu, does this look OK for trunk?
-- >8 -- Here we notice the 'this' conversion for the call f<void>() is bad, so we correctly defer instantiating it, but we end up never adding it to 'bad_fns' since missing_conversion_p for it returns false (its only argument is the already computed 'this' argument). This is not a huge deal, but it causes us to longer accept the call with -fpermissive. So if we have a non-strictly viable template candidate that has not been instantiated, then we need to add it to 'bad_fns' even if it doesn't have any missing conversions. PR c++/106760 gcc/cp/ChangeLog: * call.cc (add_candidates): Relax test for adding a candidate to 'bad_fns' to accept an uninstantiated template candidate that has no missing conversions. gcc/testsuite/ChangeLog: * g++.dg/ext/conv3.C: New test. --- gcc/cp/call.cc | 3 ++- gcc/testsuite/g++.dg/ext/conv3.C | 16 ++++++++++++++++ 2 files changed, 18 insertions(+), 1 deletion(-) create mode 100644 gcc/testsuite/g++.dg/ext/conv3.C diff --git a/gcc/cp/call.cc b/gcc/cp/call.cc index 2736f55f229..dbf42567cc9 100644 --- a/gcc/cp/call.cc +++ b/gcc/cp/call.cc @@ -6632,7 +6632,8 @@ add_candidates (tree fns, tree first_arg, const vec<tree, va_gc> *args, if (cand->viable == -1 && shortcut_bad_convs - && missing_conversion_p (cand)) + && (TREE_CODE (cand->fn) == TEMPLATE_DECL + || missing_conversion_p (cand))) { /* This candidate has been tentatively marked non-strictly viable, and we didn't compute all argument conversions for it (having diff --git a/gcc/testsuite/g++.dg/ext/conv3.C b/gcc/testsuite/g++.dg/ext/conv3.C new file mode 100644 index 00000000000..5f4b4d4cc50 --- /dev/null +++ b/gcc/testsuite/g++.dg/ext/conv3.C @@ -0,0 +1,16 @@ +// PR c++/106760 +// { dg-additional-options "-fpermissive" } + +struct S { + template<class> + int f(...); + + int g() const { + return f<void>(); // { dg-warning "discards qualifiers" } + } +}; + +int main() { + S s; + s.g(); +} -- 2.41.0.rc1.10.g9e49351c30