With the previous two patches in place, we can now extend our
deletedness diagnostic to note the other considered candidates, e.g.:
deleted16.C: In function 'int main()':
deleted16.C:10:4: error: use of deleted function 'void f(int)'
10 | f(0);
| ~^~~
deleted16.C:5:6: note: declared here
5 | void f(int) = delete;
| ^
deleted16.C:5:6: note: candidate: 'void f(int)' (deleted)
deleted16.C:6:6: note: candidate: 'void f(...)'
6 | void f(...);
| ^
deleted16.C:7:6: note: candidate: 'void f(int, int)'
7 | void f(int, int);
| ^
deleted16.C:7:6: note: candidate expects 2 arguments, 1 provided
These notes are controlled by a new command line flag -fnote-all-cands,
which also controls whether we note ignored candidates more generally.
gcc/ChangeLog:
* doc/invoke.texi (C++ Dialect Options): Document -fnote-all-cands.
gcc/c-family/ChangeLog:
* c.opt: Add -fnote-all-cands.
gcc/cp/ChangeLog:
* call.cc (print_z_candidates): Only print ignored candidates
when -fnote-all-cands is set.
(build_over_call): When diagnosing deletedness, call
print_z_candidates if -fnote-all-cands is set.
gcc/testsuite/ChangeLog:
* g++.dg/overload/error6.C: Pass -fnote-all-cands.
* g++.dg/cpp0x/deleted16.C: New test.
---
gcc/c-family/c.opt | 4 ++++
gcc/cp/call.cc | 8 +++++++-
gcc/doc/invoke.texi | 5 +++++
gcc/testsuite/g++.dg/cpp0x/deleted16.C | 25 +++++++++++++++++++++++++
gcc/testsuite/g++.dg/overload/error6.C | 1 +
5 files changed, 42 insertions(+), 1 deletion(-)
create mode 100644 gcc/testsuite/g++.dg/cpp0x/deleted16.C
diff --git a/gcc/c-family/c.opt b/gcc/c-family/c.opt
index 44b9c862c14..a76f73cc661 100644
--- a/gcc/c-family/c.opt
+++ b/gcc/c-family/c.opt
@@ -2006,6 +2006,10 @@ fnil-receivers
ObjC ObjC++ Var(flag_nil_receivers) Init(1)
Assume that receivers of Objective-C messages may be nil.
+fnote-all-cands
+C++ ObjC++ Var(flag_note_all_cands)
+Note all candidates during overload resolution failure.
+
flocal-ivars
ObjC ObjC++ Var(flag_local_ivars) Init(1)
Allow access to instance variables as if they were local declarations within
instance method implementations.
diff --git a/gcc/cp/call.cc b/gcc/cp/call.cc
index 81cc029dddb..7ace0e65096 100644
--- a/gcc/cp/call.cc
+++ b/gcc/cp/call.cc
@@ -4090,6 +4090,8 @@ print_z_candidates (location_t loc, struct z_candidate
*candidates,
{
if (only_viable_p.is_true () && candidates->viable != 1)
break;
+ if (ignored_candidate_p (candidates) && !flag_note_all_cands)
+ break;
print_z_candidate (loc, N_("candidate:"), candidates);
}
}
@@ -9933,7 +9935,11 @@ build_over_call (struct z_candidate *cand, int flags,
tsubst_flags_t complain)
if (DECL_DELETED_FN (fn))
{
if (complain & tf_error)
- mark_used (fn);
+ {
+ mark_used (fn);
+ if (cand->next && flag_note_all_cands)
+ print_z_candidates (input_location, cand, /*only_viable_p=*/false);
+ }
return error_mark_node;
}
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index 5a9284d635c..ac82299416c 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -3479,6 +3479,11 @@ Disable built-in declarations of functions that are not
mandated by
ANSI/ISO C@. These include @code{ffs}, @code{alloca}, @code{_exit},
@code{index}, @code{bzero}, @code{conjf}, and other related functions.
+@opindex fnote-all-cands
+@item -fnote-all-cands
+Permit the C++ front end to note all candidates during overload resolution
+failure, including when a deleted function is selected.
+
@opindex fnothrow-opt
@item -fnothrow-opt
Treat a @code{throw()} exception specification as if it were a
diff --git a/gcc/testsuite/g++.dg/cpp0x/deleted16.C
b/gcc/testsuite/g++.dg/cpp0x/deleted16.C
new file mode 100644
index 00000000000..506caae76b6
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/deleted16.C
@@ -0,0 +1,25 @@
+// Verify -fnote-all-cands causes us to note other candidates when a deleted
+// function is selected by overload resolution.
+// { dg-do compile { target c++11 } }
+// { dg-additional-options "-fnote-all-cands" }
+
+void f(int) = delete; // { dg-message "declared here|candidate" }
+void f(...); // { dg-message "candidate" }
+void f(int, int); // { dg-message "candidate" }
+
+// An example where the perfect candidate optimization causes us
+// to ignore function templates.
+void g(int) = delete; // { dg-message "declared here|candidate" }
+template<class T> void g(T); // { dg-message "candidate" }
+
+// An example where we have a strictly viable candidate and
+// an incompletely considered bad candidate.
+template<class T> void h(T, T) = delete; // { dg-message "declared
here|candidate" }
+void h(int*, int) = delete; // { dg-message "candidate" }
+
+int main() {
+ f(0); // { dg-error "deleted" }
+ g(0); // { dg-error "deleted" }
+ h(1, 1); // { dg-error "deleted" }
+ // { dg-error "invalid conversion" "" { target *-*-* } .-1 } when
noting 2nd cand
+}
diff --git a/gcc/testsuite/g++.dg/overload/error6.C
b/gcc/testsuite/g++.dg/overload/error6.C
index 86a12eaa8de..ac513824887 100644
--- a/gcc/testsuite/g++.dg/overload/error6.C
+++ b/gcc/testsuite/g++.dg/overload/error6.C
@@ -1,5 +1,6 @@
// Verify we note even non-template candidates when diagnosing
// overload resolution failure for a template-id.
+// { dg-additional-options "-fnote-all-cands" }
template<class T> void f(T); // { dg-message "candidate" }
void f(int); // { dg-message {candidate: 'void f\(int\)' \(ignored\)} }
--
2.42.0.482.g2e8e77cbac
