The diagnostic for the following invalid code snippet is hosed on mainline (this only affects the C++ frontend):
========================== void foo() { if (({int c[2];})) ; } ========================== bug.cc: In function 'void foo()': bug.cc:3: error: could not convert '{#'decl_expr' not supported by dump_expr#<expression error>}' to 'bool' Older versions handle this correctly: bug.cc: In function `void foo()': bug.cc:3: error: could not convert `({...})' to `bool' -- Summary: [4.0 regression] Hosed error message with statement expression Product: gcc Version: 4.0.0 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 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20148