http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53503
Bug #: 53503 Summary: [4.7 Regression] [C++0x] unexpected AST of kind ltgt_expr Classification: Unclassified Product: gcc Version: 4.7.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ AssignedTo: unassig...@gcc.gnu.org ReportedBy: lil...@gmail.com Created attachment 27510 --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=27510 Preporcessed source G++ 4.7 can't compile a one-line file with both -std=c++0x and -fno-trapping-math: $ cat a.cpp #include <cmath> $ g++ -fno-trapping-math -std=c++0x -c a.cpp In file included from a.cpp:1:0: /usr/lib/gcc/x86_64-redhat-linux/4.7.0/../../../../include/c++/4.7.0/cmath: In function ‘constexpr bool std::islessgreater(float, float)’: /usr/lib/gcc/x86_64-redhat-linux/4.7.0/../../../../include/c++/4.7.0/cmath:764:47: sorry, unimplemented: unexpected AST of kind ltgt_expr /usr/lib/gcc/x86_64-redhat-linux/4.7.0/../../../../include/c++/4.7.0/cmath:764: confused by earlier errors, bailing out Preprocessed source stored into /tmp/ccGqxqjD.out file, please attach this to your bugreport. I was using GCC 4.7.0 20120507 on Fedora 17.