[C++ Patch/RFC] PR 29143

[Paolo Carlini]

Hi,

in this very old issue we reject:

void f(int,int);
void f(int,int,int);

void g ()
{
     (&f)(1,2,3);
}

with "address of overloaded function with no contextual type information".

It seems to me that handling the ADDR_EXPR close to the beginning of 
finish_call_expr goes a long way toward fixing the problem. As regards 
the existing testsuite, besided the obvious 
g++.old-deja/g++.other/overload11.C tweak, there is the sightly more 
interesting case of g++.dg/template/call4.C: withe the patch applied, we 
start rejecting it, because we notice that propGetDouble is private. 
AFAICS, that's progress, but in principle we should detect the access 
violation even earlier, when we pass the address of propGetDouble as 
template argument: the bug is already in Bugzilla (c++/48078, maybe 
there are dups too). Thus I think this testsuite tweak is also fine.

Tested x86_64-linux.

Thanks,
Paolo.

///////////////////////


-------------- next part --------------
Index: cp/semantics.c
===================================================================
--- cp/semantics.c	(revision 204697)
+++ cp/semantics.c	(working copy)
@@ -2183,6 +2183,10 @@ finish_call_expr (tree fn, vec<tree, va_gc> **args
 	}
     }
 
+  if (TREE_CODE (fn) == ADDR_EXPR
+      && is_overloaded_fn (TREE_OPERAND (fn, 0)))
+    fn = TREE_OPERAND (fn, 0);
+
   if (is_overloaded_fn (fn))
     fn = baselink_for_fns (fn);
 
Index: testsuite/g++.dg/overload/addr2.C
===================================================================
--- testsuite/g++.dg/overload/addr2.C	(revision 0)
+++ testsuite/g++.dg/overload/addr2.C	(working copy)
@@ -0,0 +1,13 @@
+// PR c++/29143
+
+void f(int);
+
+void g(int,int);
+void g(int,int,int);
+
+void
+h ()
+{
+  (&f)(1);
+  (&g)(1,2,3);
+}
Index: testsuite/g++.dg/template/call4.C
===================================================================
--- testsuite/g++.dg/template/call4.C	(revision 204697)
+++ testsuite/g++.dg/template/call4.C	(working copy)
@@ -2,7 +2,7 @@
 
 class OFX_PropertySuiteV1
 {
-  static int propGetDouble ();
+  static int propGetDouble ();       // { dg-error "private" }
 };
 template<int dimension,
 	 class T,
@@ -12,7 +12,7 @@ struct OFX_AnimatedNumberParam
 {
   virtual int paramSetValueAtTime()
   {
-    return PROPGET();
+    return PROPGET();                // { dg-error "context" }
   }
 };
 void  f()
Index: testsuite/g++.old-deja/g++.other/overload11.C
===================================================================
--- testsuite/g++.old-deja/g++.other/overload11.C	(revision 204697)
+++ testsuite/g++.old-deja/g++.other/overload11.C	(working copy)
@@ -32,7 +32,7 @@ int main (int argc, char **argv)
   void (*vptr) ();
   
   (ovl) (1);                // ok
-  (&ovl) (1);               // { dg-error "" } not suitable for overload resolution
+  (&ovl) (1);               // ok
   (ovl) ();                 // { dg-error "" } no matching candidates
   // { dg-message "candidate" "candidate note" { target *-*-* } 36 }
   (&ovl) ();                // { dg-error "" } not suitable for overload resolution