mingw: make argv2 in try_shell_exec() non-const

Prepare for a stricter type check in COPY_ARRAY by removing the const
qualifier of argv2, like we already do to placate Visual Studio.  We
have to add it back using explicit casts when actually using the
variable, unfortunately, because GCC (rightly) refuses to add it
implicitly.  Similar casts are already used in mingw_execv().

Signed-off-by: René Scharfe <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: rscharfe

compat/mingw.c

@@ -1839,16 +1839,13 @@ static int try_shell_exec(const char *cmd, char *const *argv)
 	if (prog) {
 		int exec_id;
 		int argc = 0;
-#ifndef _MSC_VER
-		const
-#endif
 		char **argv2;
 		while (argv[argc]) argc++;
 		ALLOC_ARRAY(argv2, argc + 1);
 		argv2[0] = (char *)cmd;	/* full path to the script file */
 		COPY_ARRAY(&argv2[1], &argv[1], argc);
-		exec_id = trace2_exec(prog, argv2);
-		pid = mingw_spawnv(prog, argv2, 1);
+		exec_id = trace2_exec(prog, (const char **)argv2);
+		pid = mingw_spawnv(prog, (const char **)argv2, 1);
 		if (pid >= 0) {
 			int status;
 			if (waitpid(pid, &status, 0) < 0)