Re: [PATCH] c++: add "'requires' only available with ..." note

[Jason Merrill via Gcc-patches]

On 4/24/20 3:52 PM, Patrick Palka wrote:

This adds a note suggesting to enable concepts whenever 'requires' is parsed as
an invalid type name with concepts disabled.

Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK to commit?


OK.


gcc/cp/ChangeLog:

* parser.c (cp_parser_diagnose_invalid_type_name): Suggest to enable
concepts if the invalid identifier is 'requires'.

gcc/testsuite/ChangeLog:

* g++.dg/concepts/diagnostic11.C: New test.
---
  gcc/cp/parser.c  | 3 +++
  gcc/testsuite/g++.dg/concepts/diagnostic11.C | 6 ++
  2 files changed, 9 insertions(+)
  create mode 100644 gcc/testsuite/g++.dg/concepts/diagnostic11.C

diff --git a/gcc/cp/parser.c b/gcc/cp/parser.c
index 47e3f2bbd3d..337f22d2784 100644
--- a/gcc/cp/parser.c
+++ b/gcc/cp/parser.c
@@ -3378,6 +3378,9 @@ cp_parser_diagnose_invalid_type_name (cp_parser *parser, 
tree id,
else if (!flag_concepts && id == ridpointers[(int)RID_CONCEPT])
inform (location, "% only available with %<-std=c++2a%> or "
"%<-fconcepts%>");
+  else if (!flag_concepts && id == ridpointers[(int)RID_REQUIRES])
+   inform (location, "% only available with %<-std=c++2a%> or "
+   "%<-fconcepts%>");
else if (processing_template_decl && current_class_type
   && TYPE_BINFO (current_class_type))
{
diff --git a/gcc/testsuite/g++.dg/concepts/diagnostic11.C 
b/gcc/testsuite/g++.dg/concepts/diagnostic11.C
new file mode 100644
index 000..7c60912352a
--- /dev/null
+++ b/gcc/testsuite/g++.dg/concepts/diagnostic11.C
@@ -0,0 +1,6 @@
+// { dg-do compile { target c++17_only } }
+
+template 
+  requires B // { dg-error ".requires. does not name a type" }
+// { dg-message ".requires. only available with" "" { target *-*-* } .-1 }
+void foo() { }

[PATCH] c++: add "'requires' only available with ..." note

[Patrick Palka via Gcc-patches]

This adds a note suggesting to enable concepts whenever 'requires' is parsed as
an invalid type name with concepts disabled.

Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK to commit?

gcc/cp/ChangeLog:

* parser.c (cp_parser_diagnose_invalid_type_name): Suggest to enable
concepts if the invalid identifier is 'requires'.

gcc/testsuite/ChangeLog:

* g++.dg/concepts/diagnostic11.C: New test.
---
 gcc/cp/parser.c  | 3 +++
 gcc/testsuite/g++.dg/concepts/diagnostic11.C | 6 ++
 2 files changed, 9 insertions(+)
 create mode 100644 gcc/testsuite/g++.dg/concepts/diagnostic11.C

diff --git a/gcc/cp/parser.c b/gcc/cp/parser.c
index 47e3f2bbd3d..337f22d2784 100644
--- a/gcc/cp/parser.c
+++ b/gcc/cp/parser.c
@@ -3378,6 +3378,9 @@ cp_parser_diagnose_invalid_type_name (cp_parser *parser, 
tree id,
   else if (!flag_concepts && id == ridpointers[(int)RID_CONCEPT])
inform (location, "% only available with %<-std=c++2a%> or "
"%<-fconcepts%>");
+  else if (!flag_concepts && id == ridpointers[(int)RID_REQUIRES])
+   inform (location, "% only available with %<-std=c++2a%> or "
+   "%<-fconcepts%>");
   else if (processing_template_decl && current_class_type
   && TYPE_BINFO (current_class_type))
{
diff --git a/gcc/testsuite/g++.dg/concepts/diagnostic11.C 
b/gcc/testsuite/g++.dg/concepts/diagnostic11.C
new file mode 100644
index 000..7c60912352a
--- /dev/null
+++ b/gcc/testsuite/g++.dg/concepts/diagnostic11.C
@@ -0,0 +1,6 @@
+// { dg-do compile { target c++17_only } }
+
+template 
+  requires B // { dg-error ".requires. does not name a type" }
+// { dg-message ".requires. only available with" "" { target *-*-* } .-1 }
+void foo() { }
-- 
2.26.2.266.ge870325ee8