Preserve the location of explicitly defaulted functions.

	* decl2.c (mark_used): Don't clobber DECL_SOURCE_LOCATION on
	explicitly defaulted functions.
	* method.c (synthesize_method): Likewise.

From-SVN: r276902

gcc/cp/ChangeLog

+2019-10-11  Jason Merrill  <jason@redhat.com>
+
+	* decl2.c (mark_used): Don't clobber DECL_SOURCE_LOCATION on
+	explicitly defaulted functions.
+	* method.c (synthesize_method): Likewise.
+
 2019-10-11  Jakub Jelinek  <jakub@redhat.com>
 
 	PR c++/91987

gcc/cp/decl2.c

@@ -5588,7 +5588,8 @@ mark_used (tree decl, tsubst_flags_t complain)
       /* Remember the current location for a function we will end up
 	 synthesizing.  Then we can inform the user where it was
 	 required in the case of error.  */
-      DECL_SOURCE_LOCATION (decl) = input_location;
+      if (DECL_ARTIFICIAL (decl))
+	DECL_SOURCE_LOCATION (decl) = input_location;
 
       /* Synthesizing an implicitly defined member function will result in
 	 garbage collection.  We must treat this situation as if we were

gcc/cp/method.c

@@ -892,7 +892,7 @@ synthesize_method (tree fndecl)
 
   /* Reset the source location, we might have been previously
      deferred, and thus have saved where we were first needed.  */
-  if (!DECL_INHERITED_CTOR (fndecl))
+  if (DECL_ARTIFICIAL (fndecl) && !DECL_INHERITED_CTOR (fndecl))
     DECL_SOURCE_LOCATION (fndecl)
       = DECL_SOURCE_LOCATION (TYPE_NAME (DECL_CONTEXT (fndecl)));
 
@@ -953,8 +953,9 @@ synthesize_method (tree fndecl)
   pop_deferring_access_checks ();
 
   if (error_count != errorcount || warning_count != warningcount + werrorcount)
-    inform (input_location, "synthesized method %qD first required here",
-	    fndecl);
+    if (DECL_ARTIFICIAL (fndecl))
+      inform (input_location, "synthesized method %qD first required here",
+	      fndecl);
 }
 
 /* Build a reference to type TYPE with cv-quals QUALS, which is an