On Thu, Apr 08, 2021 at 04:37:00PM -0400, Patrick Palka wrote:
> On Thu, 8 Apr 2021, Marek Polacek via Gcc-patches wrote:
>
> > When we have a member function with auto parameter like this:
> >
> > struct S {
> > void f(auto);
> > };
> >
> > cp_parser_member_declaration -> grokfield produces a FUNCTION_DECL
> > "void S::foo(auto:1)", and then finish_fully_implicit_template turns
> > that FUNCTION_DECL into a TEMPLATE_DECL. The bug here is that we only
> > call cp_parser_save_default_args for a FUNCTION_DECL. As a consequence,
> > abbrev10.C is rejected because we complain that the default argument has
> > not been defined, and abbrev11.C ICEs, because we don't re-parse the
> > delayed noexcept, so the DEFERRED_PARSE tree leaks into tsubst* where we
> > crash. This patch fixes both issues.
> >
> > Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk/10.4?
> >
> > gcc/cp/ChangeLog:
> >
> > PR c++/99806
> > * parser.c (cp_parser_member_declaration): Call
> > cp_parser_save_default_args even for function templates.
> > (cp_parser_save_default_args): Extract the function declaration
> > from a function template.
> >
> > gcc/testsuite/ChangeLog:
> >
> > PR c++/99806
> > * g++.dg/concepts/abbrev10.C: New test.
> > * g++.dg/concepts/abbrev11.C: New test.
> > ---
> > gcc/cp/parser.c | 8 +++++---
> > gcc/testsuite/g++.dg/concepts/abbrev10.C | 18 ++++++++++++++++++
> > gcc/testsuite/g++.dg/concepts/abbrev11.C | 10 ++++++++++
> > 3 files changed, 33 insertions(+), 3 deletions(-)
> > create mode 100644 gcc/testsuite/g++.dg/concepts/abbrev10.C
> > create mode 100644 gcc/testsuite/g++.dg/concepts/abbrev11.C
> >
> > diff --git a/gcc/cp/parser.c b/gcc/cp/parser.c
> > index 59adac4492a..eef6bb3003e 100644
> > --- a/gcc/cp/parser.c
> > +++ b/gcc/cp/parser.c
> > @@ -26433,7 +26433,8 @@ cp_parser_member_declaration (cp_parser* parser)
> > || !DECL_DECLARES_FUNCTION_P (decl))
> > finish_member_declaration (decl);
> >
> > - if (TREE_CODE (decl) == FUNCTION_DECL)
> > + if (TREE_CODE (decl) == FUNCTION_DECL
> > + || DECL_FUNCTION_TEMPLATE_P (decl))
>
> I guess you could use DECL_DECLARES_FUNCTION_P here.
Right, thanks.
> > cp_parser_save_default_args (parser, decl);
> > else if (TREE_CODE (decl) == FIELD_DECL
> > && DECL_INITIAL (decl))
> > @@ -30959,9 +30960,10 @@ cp_parser_late_parsing_for_member (cp_parser*
> > parser, tree member_function)
> > static void
> > cp_parser_save_default_args (cp_parser* parser, tree decl)
> > {
> > - tree probe;
> > + if (DECL_FUNCTION_TEMPLATE_P (decl))
> > + decl = DECL_TEMPLATE_RESULT (decl);
>
> Not sure if it'd be an improvement, but could use STRIP_TEMPLATE here
> instead (or perhaps on the caller side).
Might as well. How's this?
Bootstrapped/regtested on x86_64-pc-linux-gnu, ok for trunk/10?
-- >8 --
When we have a member function with auto parameter like this:
struct S {
void f(auto);
};
cp_parser_member_declaration -> grokfield produces a FUNCTION_DECL
"void S::foo(auto:1)", and then finish_fully_implicit_template turns
that FUNCTION_DECL into a TEMPLATE_DECL. The bug here is that we only
call cp_parser_save_default_args for a FUNCTION_DECL. As a consequence,
abbrev10.C is rejected because we complain that the default argument has
not been defined, and abbrev11.C ICEs, because we don't re-parse the
delayed noexcept, so the DEFERRED_PARSE tree leaks into tsubst* where we
crash. This patch fixes both issues.
gcc/cp/ChangeLog:
PR c++/99806
* parser.c (cp_parser_member_declaration): Call
cp_parser_save_default_args even for function templates. Use
STRIP_TEMPLATE on the declaration we're passing.
gcc/testsuite/ChangeLog:
PR c++/99806
* g++.dg/concepts/abbrev10.C: New test.
* g++.dg/concepts/abbrev11.C: New test.
---
gcc/cp/parser.c | 4 ++--
gcc/testsuite/g++.dg/concepts/abbrev10.C | 18 ++++++++++++++++++
gcc/testsuite/g++.dg/concepts/abbrev11.C | 10 ++++++++++
3 files changed, 30 insertions(+), 2 deletions(-)
create mode 100644 gcc/testsuite/g++.dg/concepts/abbrev10.C
create mode 100644 gcc/testsuite/g++.dg/concepts/abbrev11.C
diff --git a/gcc/cp/parser.c b/gcc/cp/parser.c
index 59adac4492a..e6e6ed72a42 100644
--- a/gcc/cp/parser.c
+++ b/gcc/cp/parser.c
@@ -26433,8 +26433,8 @@ cp_parser_member_declaration (cp_parser* parser)
|| !DECL_DECLARES_FUNCTION_P (decl))
finish_member_declaration (decl);
- if (TREE_CODE (decl) == FUNCTION_DECL)
- cp_parser_save_default_args (parser, decl);
+ if (DECL_DECLARES_FUNCTION_P (decl))
+ cp_parser_save_default_args (parser, STRIP_TEMPLATE (decl));
else if (TREE_CODE (decl) == FIELD_DECL
&& DECL_INITIAL (decl))
/* Add DECL to the queue of NSDMI to be parsed later. */
diff --git a/gcc/testsuite/g++.dg/concepts/abbrev10.C
b/gcc/testsuite/g++.dg/concepts/abbrev10.C
new file mode 100644
index 00000000000..b611346e926
--- /dev/null
+++ b/gcc/testsuite/g++.dg/concepts/abbrev10.C
@@ -0,0 +1,18 @@
+// PR c++/99806
+// { dg-do compile { target c++14 } }
+// { dg-additional-options "-fconcepts" }
+
+struct S {
+ void f(auto, auto, int = 3);
+ void f2(auto, auto, int = 3) { }
+ template<typename T> static T g(T, auto, int = 3);
+};
+
+void
+g ()
+{
+ S::g(1, 2);
+ S s;
+ s.f(1, 2);
+ s.f2(1, 2);
+}
diff --git a/gcc/testsuite/g++.dg/concepts/abbrev11.C
b/gcc/testsuite/g++.dg/concepts/abbrev11.C
new file mode 100644
index 00000000000..ddb479313df
--- /dev/null
+++ b/gcc/testsuite/g++.dg/concepts/abbrev11.C
@@ -0,0 +1,10 @@
+// PR c++/99806
+// { dg-do compile { target c++14 } }
+// { dg-additional-options "-fconcepts" }
+
+template <typename T> concept C = requires (T a) { a.f(0); };
+struct S {
+ void f(auto) noexcept(B);
+ static constexpr bool B = true;
+};
+static_assert(C<S>, "");
base-commit: 123b3e03c911a43054c1f88f5d3110e1d084dd4e
--
2.30.2
