[C++ Patch] PR 51230

[Paolo Carlini]

Hi,

apparently in the new deductions notes we are not handling correctly 
non-type parameters in some messages, like in:

template<int> struct A {};

template<int N> void foo(A<N>, A<N>);

void bar()
{
  foo(A<0>(), A<1>());
}

we use %qT in unify_inconsistency and the output is garbled. The below 
is the most compact fix I have been able to figure out, but of course 
other solutions are possible, like separate error messages for non-type 
(TYPE_P (parm) to tell which appears to work fine), etc. Tested 
x86_64-linux.

Thanks,
Paolo.

//////////////////////
/cp
2011-11-20  Paolo Carlini  <paolo.carl...@oracle.com>

        PR c++/51230
        * pt.c (unify_inconsistency): Handle non-type parameters better.

/cp
2011-11-20  Paolo Carlini  <paolo.carl...@oracle.com>

        PR c++/51230
        * g++.dg/template/error46.C: New.

Index: testsuite/g++.dg/template/error46.C
===================================================================
--- testsuite/g++.dg/template/error46.C (revision 0)
+++ testsuite/g++.dg/template/error46.C (revision 0)
@@ -0,0 +1,11 @@
+// PR c++/51230
+
+template<int> struct A {}; 
+
+template<int N> void foo(A<N>, A<N>); // { dg-message "template" }
+
+void bar()
+{
+  foo(A<0>(), A<1>()); // { dg-error "no matching" }
+}
+// { dg-message "candidate|parameter 'N' ('0' and '1')" { target *-*-* } 9 }
Index: cp/pt.c
===================================================================
--- cp/pt.c     (revision 181521)
+++ cp/pt.c     (working copy)
@@ -5501,7 +5501,7 @@ unify_inconsistency (bool explain_p, tree parm, tr
 {
   if (explain_p)
     inform (input_location,
-           "  deduced conflicting types for parameter %qT (%qT and %qT)",
+           "  conflicting deductions for parameter %qE (%qE and %qE)",
            parm, first, second);
   return 1;
 }