diff mbox series

[pushed] c++: result location and explicit inst [PR108496]

Message ID 20230123190936.4161568-1-jason@redhat.com
State New
Headers show
Series [pushed] c++: result location and explicit inst [PR108496] | expand

Commit Message

Jason Merrill Jan. 23, 2023, 7:09 p.m. UTC 
Tested x86_64-pc-linux-gnu, applying to trunk.

-- 8< --

In r13-4469 we started to build the RESULT_DECL in grokdeclarator, while we
still know the location of the return type.  But in this testcase, we hit
that code again when parsing the explicit instantiation, and clobber the
DECL_RESULT that was previously used in parsing the function.  So, only set
DECL_RESULT if it isn't already set.

	PR c++/108496

gcc/cp/ChangeLog:

	* decl.cc (grokdeclarator): Check whether DECL_RESULT is already
	set.

gcc/testsuite/ChangeLog:

	* g++.dg/template/explicit-instantiation5.C: New test.
---
 gcc/cp/decl.cc                                    |  6 +++++-
 .../g++.dg/template/explicit-instantiation5.C     | 15 +++++++++++++++
 2 files changed, 20 insertions(+), 1 deletion(-)
 create mode 100644 gcc/testsuite/g++.dg/template/explicit-instantiation5.C


base-commit: 208c6678c25bd9a11e6c5911a4c123cb6b7f3d6e
diff mbox series

Patch

diff --git a/gcc/cp/decl.cc b/gcc/cp/decl.cc
index 75ddf8016b5..d606b31d7a7 100644
--- a/gcc/cp/decl.cc
+++ b/gcc/cp/decl.cc
@@ -14776,7 +14776,9 @@  grokdeclarator (const cp_declarator *declarator,
       {
 	/* If we saw a return type, record its location.  */
 	location_t loc = declspecs->locations[ds_type_spec];
-	if (loc != UNKNOWN_LOCATION)
+	if (loc == UNKNOWN_LOCATION)
+	  /* Build DECL_RESULT in start_preparsed_function.  */;
+	else if (!DECL_RESULT (decl))
 	  {
 	    tree restype = TREE_TYPE (TREE_TYPE (decl));
 	    tree resdecl = build_decl (loc, RESULT_DECL, 0, restype);
@@ -14784,6 +14786,8 @@  grokdeclarator (const cp_declarator *declarator,
 	    DECL_IGNORED_P (resdecl) = 1;
 	    DECL_RESULT (decl) = resdecl;
 	  }
+	else if (funcdef_flag)
+	  DECL_SOURCE_LOCATION (DECL_RESULT (decl)) = loc;
       }
 
     /* Record constancy and volatility on the DECL itself .  There's
diff --git a/gcc/testsuite/g++.dg/template/explicit-instantiation5.C b/gcc/testsuite/g++.dg/template/explicit-instantiation5.C
new file mode 100644
index 00000000000..7bc007c8107
--- /dev/null
+++ b/gcc/testsuite/g++.dg/template/explicit-instantiation5.C
@@ -0,0 +1,15 @@ 
+// PR c++/108496
+
+struct S { long a, b, c; } s;
+
+template <int, typename>
+S foo (S);
+
+template <>
+S
+foo <0, long> (S)
+{
+  return s;
+}
+
+template S foo <0, long> (S);