[cfe-dev] Crash with C++exception. Bug in codegen, or in the developer ?

[Jean-Daniel Dupas]

Hello,

While running the following code,  it crashes due to an invalid free operation:

exc(8657) malloc: *** error for object 0x7f97c14039e0: pointer being freed was not allocated
*** set a breakpoint in malloc_error_break to debug
fish: Job 1, './exc' terminated by signal SIGABRT (Abort)

--- --- --- --- --- 
#include <string>

class Error {
public:
  explicit inline Error(const std::string &str) noexcept {}
};

std::string _cxx_strfmt() noexcept { return std::string(); }

int main(int argc, char **argv) {
  try {
    throw Error(_cxx_strfmt());
  } catch (...) {}
}
------

compiled using 
clang++ -std=c++11  exc.cpp

I can't see what is wrong with this code, but if I remove the noexcept declaration (either one), it stop crashing and run as expected.

Is this something I'm doing wrong, or this is a subtle clang bug ? 

I attach the llvm ir generate with noexcept (exc-crash.s) and the one without (exc.s)

If this is a bug in clang, tell me, I will fill a report.

Thanks

-- Jean-Daniel



-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/cfe-dev/attachments/20120713/6d145b7a/attachment.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: exc.s
Type: application/octet-stream
Size: 5378 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/cfe-dev/attachments/20120713/6d145b7a/attachment.obj>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/cfe-dev/attachments/20120713/6d145b7a/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: exc-crash.s
Type: application/octet-stream
Size: 5462 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/cfe-dev/attachments/20120713/6d145b7a/attachment-0001.obj>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.llvm.org/pipermail/cfe-dev/attachments/20120713/6d145b7a/attachment-0002.html>