On mainline I get a hosed error message for the following invalid code snippet:
======================================================== template<int> struct A {}; template<int N> void foo(const A<N> &a) { -A<N>(a); } void bar() { foo(A<0>()); } ======================================================== The error message reads: bug.cc: In function 'void foo(const A<N>&) [with int N = 0]': bug.cc:7: instantiated from here bug.cc:3: error: no match for 'operator-' in '-((const A<0>&)#'convert_expr' not supported by dump_expr#<expression error>)' With gcc 4.0.0 I get the following message instead: bug.cc: In function 'void foo(const A<N>&) [with int N = 0]': bug.cc:7: instantiated from here bug.cc:3: error: no match for 'operator-' in '-((const A<0>&)(+ a))' I don't know why the plus sign appears before "a", but this suggests that the regression is related to the recent introduction of UNARY_PLUS_EXPR: http://gcc.gnu.org/ml/gcc-patches/2005-05/msg02580.html -- Summary: [4.1 regression] pretty printer confusion Product: gcc Version: 4.1.0 Status: UNCONFIRMED Keywords: diagnostic, monitored Severity: normal Priority: P2 Component: c++ AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: reichelt at gcc dot gnu dot org CC: gcc-bugs at gcc dot gnu dot org,giovannibajo at gcc dot gnu dot org,roger at eyesopen dot com http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21930