Unable to break on function name in gdb mingw

Question

My program has multiple files, and I compile with g++ -g.
When I try to break on WinMain, it says Function not defined, but when I show listing it appears right there.

(gdb) list Winmain.cpp:237
237     // WinMain
238     int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance
pCmdLine, int nCmdShow) {
239
240             //Debuging mode
(gdb)
241
242             // IO thread  ;;;; in charge of writing stuff to files
reak the mem thread
243             // /var/log/simulator.log
244             freopen ("debug.txt", "w", stdout);
245
246             // Strings
247             static TCHAR szWindowClass[] = TEXT("myWnd"); // std::s
indowClass = "myWnd";
248             static TCHAR szTitle[] = _T("Virtual Map");   // std::s
itle = "Virtual map";
249
250             // Windows Structure
(gdb) b Winmain.cpp:WinMain
Function "WinMain" not defined in "Winmain.cpp".
Make breakpoint pending on future shared library load? (y or [n]) n

I can break with b Winmain.cpp:238, but why doesn't it work by name?

mingw32 on windows7
GNU gdb (GDB) 7.6.1

Answer 1

WinMain() is a __stdcall function; (that knowledge is conveyed, with typical Microsoft obfuscation, by the WINAPI qualifier). Thus, its publicly visible name becomes qualified as WinMain@16() ; you should set your gdb breakpoint on this qualified name.