crt: exe: Invoke gcc c++ constructors after msvc c++ constructors

Function __main() is function for executing gcc c++ constructors. Move it
into guarded code which prevents duplicate code execution, after executing
msvc c++ constructors (__xc_a-__xc_z callbacks).

Signed-off-by: Martin Storsjö <martin@martin.st>

mingw-w64-crt/crt/crtexe.c

diff --git a/mingw-w64-crt/crt/crtexe.c b/mingw-w64-crt/crt/crtexe.c
index 0f79c0a..00221ea 100644
--- a/mingw-w64-crt/crt/crtexe.c
+++ b/mingw-w64-crt/crt/crtexe.c
@@ -216,6 +216,7 @@
 	  _amsg_exit (8); /* _RT_SPACEARG */
 
 	_initterm (__xc_a, __xc_z);
+	__main (); /* C++ initialization. */
 
 	__native_startup_state = __initialized;
       }
@@ -228,7 +229,6 @@
       __dyn_tls_init_callback (NULL, DLL_THREAD_ATTACH, NULL);
 
     duplicate_ppstrings (argc, &argv);
-    __main (); /* C++ initialization. */
 #ifdef _UNICODE
     __winitenv = envp;
 #else