In fn_type_unifcation, we are passing NULL_TREE as the 'in_decl' parameter to coerce_template_parms, and this is causing template type/value mismatch error messages to get suppressed regardless of the value of 'complain'.
This means that when substitution into a function template fails due to a type/value mismatch between a template parameter and the provided template argument, we just say "template argument deduction/substitution failed:" without a followup explanation of the failure. Fix this by passing 'fn' instead of NULL_TREE to coerce_template_parms. Passes 'make check-c++', does this look OK to commit after a full bootstrap and regtest? gcc/cp/ChangeLog: * pt.c (fn_type_unification): Pass 'fn' instead of NULL_TREE as the 'in_decl' parameter to coerce_template_parms. gcc/testsuite/ChangeLog: * g++.dg/cpp2a/concepts-ts4.C: Expect a "type/value mismatch" diagnostic. * g++.dg/cpp2a/concepts-ts6.C: Likewise. * g++.dg/template/error56.C: Likewise. * g++.dg/template/error59.C: New test. libstdc++-v3/ChangeLog: * testsuite/20_util/pair/astuple/get_neg.cc: Prune "type/value mismatch" messages. * testsuite/20_util/tuple/element_access/get_neg.cc: Likewise. --- gcc/cp/pt.c | 2 +- gcc/testsuite/g++.dg/cpp2a/concepts-ts4.C | 2 ++ gcc/testsuite/g++.dg/cpp2a/concepts-ts6.C | 4 +++- gcc/testsuite/g++.dg/template/error56.C | 2 ++ gcc/testsuite/g++.dg/template/error59.C | 11 +++++++++++ .../testsuite/20_util/pair/astuple/get_neg.cc | 1 + .../testsuite/20_util/tuple/element_access/get_neg.cc | 1 + 7 files changed, 21 insertions(+), 2 deletions(-) create mode 100644 gcc/testsuite/g++.dg/template/error59.C diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c index c6091127225..52bb6f34d6a 100644 --- a/gcc/cp/pt.c +++ b/gcc/cp/pt.c @@ -21088,7 +21088,7 @@ fn_type_unification (tree fn, /* Adjust any explicit template arguments before entering the substitution context. */ explicit_targs - = (coerce_template_parms (tparms, explicit_targs, NULL_TREE, + = (coerce_template_parms (tparms, explicit_targs, fn, complain|tf_partial, /*require_all_args=*/false, /*use_default_args=*/false)); diff --git a/gcc/testsuite/g++.dg/cpp2a/concepts-ts4.C b/gcc/testsuite/g++.dg/cpp2a/concepts-ts4.C index aa96621d9cf..2b0fd1b8deb 100644 --- a/gcc/testsuite/g++.dg/cpp2a/concepts-ts4.C +++ b/gcc/testsuite/g++.dg/cpp2a/concepts-ts4.C @@ -31,4 +31,6 @@ void driver() fn<0>(); // OK fn<-1>(); // { dg-error "" } fn<int>(); // { dg-error "no matching function" } + // { dg-error "type/value mismatch at argument 1" "" { target *-*-* } .-1 } + // { dg-message "expected a constant of type .int., got .int." "" { target *-*-* } .-2 } } diff --git a/gcc/testsuite/g++.dg/cpp2a/concepts-ts6.C b/gcc/testsuite/g++.dg/cpp2a/concepts-ts6.C index bf665aa6308..e3dff54c83d 100644 --- a/gcc/testsuite/g++.dg/cpp2a/concepts-ts6.C +++ b/gcc/testsuite/g++.dg/cpp2a/concepts-ts6.C @@ -25,6 +25,8 @@ void driver1() { f<X>(); f<int>(); // { dg-error "no matching function for call" } + // { dg-error "type/value mismatch at argument 1" "" { target *-*-* } .-1 } + // { dg-message "expected a class template, got .int." "" { target *-*-* } .-2 } S2<int> s2a; S2<char, signed char, unsigned char> s2b; @@ -69,4 +71,4 @@ void driver2() S6<void, void> s6a; S6<void, int> s6c; // { dg-error "template constraint failure" } S6<void, void, void> s6b; // { dg-error "wrong number of template arguments" } -} \ No newline at end of file +} diff --git a/gcc/testsuite/g++.dg/template/error56.C b/gcc/testsuite/g++.dg/template/error56.C index 3eda04c3225..e85471a50b0 100644 --- a/gcc/testsuite/g++.dg/template/error56.C +++ b/gcc/testsuite/g++.dg/template/error56.C @@ -9,4 +9,6 @@ struct A int main() { A().f<1>(); // { dg-error "f<1>" } + // { dg-error "type/value mismatch at argument 1" "" { target *-*-* } .-1 } + // { dg-message "expected a type, got .1." "" { target *-*-* } .-2 } } diff --git a/gcc/testsuite/g++.dg/template/error59.C b/gcc/testsuite/g++.dg/template/error59.C new file mode 100644 index 00000000000..f81a28c2f1a --- /dev/null +++ b/gcc/testsuite/g++.dg/template/error59.C @@ -0,0 +1,11 @@ +template<int N> struct S { }; + +template<template<typename> class TT> +void foo(); + +void bar() +{ + foo<S>(); // { dg-error "no matching function" } + // { dg-error "type/value mismatch at argument 1" "" { target *-*-* } .-1 } + // { dg-message "expected a template of type .template<class> class TT., got .template<int N> struct S." "" { target *-*-* } .-2 } +} diff --git a/libstdc++-v3/testsuite/20_util/pair/astuple/get_neg.cc b/libstdc++-v3/testsuite/20_util/pair/astuple/get_neg.cc index bcf3940e16d..1f76aef6d73 100644 --- a/libstdc++-v3/testsuite/20_util/pair/astuple/get_neg.cc +++ b/libstdc++-v3/testsuite/20_util/pair/astuple/get_neg.cc @@ -27,3 +27,4 @@ void test01() } // { dg-prune-output "tuple_element<2" } +// { dg-prune-output "type/value mismatch" } diff --git a/libstdc++-v3/testsuite/20_util/tuple/element_access/get_neg.cc b/libstdc++-v3/testsuite/20_util/tuple/element_access/get_neg.cc index 8488e287a98..03ad77215d2 100644 --- a/libstdc++-v3/testsuite/20_util/tuple/element_access/get_neg.cc +++ b/libstdc++-v3/testsuite/20_util/tuple/element_access/get_neg.cc @@ -61,3 +61,4 @@ test03() } // { dg-prune-output "no type named .type" } +// { dg-prune-output "type/value mismatch" } -- 2.26.2.561.g07d8ea56f2