From: Patrick Palka <ppalka@redhat.com>
Date: Sun, 7 May 2023 15:57:22 +0000 (-0400)
Subject: c++: parenthesized -> resolving to static data member [PR98283]
X-Git-Tag: basepoints/gcc-15~9579
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e4f1ea5d8b96fc9fbe4fc0e0e0a4938ceeef092f;p=thirdparty%2Fgcc.git

c++: parenthesized -> resolving to static data member [PR98283]

Here we're neglecting to propagate parenthesized-ness when the
member access (this->m) resolves to a static data member (and
thus finish_class_member_access_expr yields a VAR_DECL instead
of a COMPONENT_REF).

	PR c++/98283

gcc/cp/ChangeLog:

	* pt.cc (tsubst_copy_and_build) <case COMPONENT_REF>: Propagate
	REF_PARENTHESIZED_P more generally via force_paren_expr.
	* semantics.cc (force_paren_expr): Document default argument.

gcc/testsuite/ChangeLog:

	* g++.dg/cpp1y/paren6.C: New test.
---

diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc
index ee4a2f313430..de95e128c729 100644
--- a/gcc/cp/pt.cc
+++ b/gcc/cp/pt.cc
@@ -21520,8 +21520,8 @@ tsubst_copy_and_build (tree t,
 	r = finish_class_member_access_expr (object, member,
 					     /*template_p=*/false,
 					     complain);
-	if (TREE_CODE (r) == COMPONENT_REF)
-	  REF_PARENTHESIZED_P (r) = REF_PARENTHESIZED_P (t);
+	if (REF_PARENTHESIZED_P (t))
+	  r = force_paren_expr (r);
 	RETURN (r);
       }
 
diff --git a/gcc/cp/semantics.cc b/gcc/cp/semantics.cc
index 474da71bff62..13c6582b6289 100644
--- a/gcc/cp/semantics.cc
+++ b/gcc/cp/semantics.cc
@@ -2070,7 +2070,7 @@ finish_mem_initializers (tree mem_inits)
    right result.  If EVEN_UNEVAL, do this even in unevaluated context.  */
 
 tree
-force_paren_expr (tree expr, bool even_uneval)
+force_paren_expr (tree expr, bool even_uneval /* = false */)
 {
   /* This is only needed for decltype(auto) in C++14.  */
   if (cxx_dialect < cxx14)
diff --git a/gcc/testsuite/g++.dg/cpp1y/paren6.C b/gcc/testsuite/g++.dg/cpp1y/paren6.C
new file mode 100644
index 000000000000..812a99ca91cf
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp1y/paren6.C
@@ -0,0 +1,14 @@
+// PR c++/98283
+// { dg-do compile { target c++14 } }
+
+struct A {
+  static int m;
+};
+
+template<class T>
+struct B : T {
+  decltype(auto) f() { return (this->m);  }
+};
+
+using type = decltype(B<A>().f());
+using type = int&;