Add myargmalloc boolean to detect whether we allocated myargv ourselves or not, so we don't free myargv if we didn't

src/m_argv.c

@@ -25,6 +25,10 @@ INT32 myargc;
 */
 char **myargv;
 
+/** \brief did we alloc myargv ourselves?
+*/
+boolean myargmalloc = false;
+
 /**	\brief founded the parm
 */
 static INT32 found;
@@ -176,6 +180,7 @@ void M_FindResponseFile(void)
 				free(file);
 				I_Error("Not enough memory to read response file");
 			}
+			myargmalloc = true; // mark as having been allocated by us
 			memset(myargv, 0, sizeof (char *) * MAXARGVS);
 			myargv[0] = firstargv;
 

src/m_argv.h

@@ -19,6 +19,7 @@
 //
 extern INT32 myargc;
 extern char **myargv;
+extern boolean myargmalloc;
 
 // Returns the position of the given parameter in the arg list (0 if not found).
 INT32 M_CheckParm(const char *check);

src/sdl/i_system.c

@@ -2139,6 +2139,7 @@ void I_Quit(void)
 		printf("\r");
 		ShowEndTxt();
 	}
+	if (myargmalloc)
 		free(myargv); // Deallocate allocated memory
 death:
 	W_Shutdown();

src/sdl12/i_system.c

@@ -2301,6 +2301,7 @@ void I_Quit(void)
 		printf("\r");
 		ShowEndTxt();
 	}
+	if (myargmalloc)
 		free(myargv); // Deallocate allocated memory
 death:
 	W_Shutdown();

src/win32/win_sys.c

@@ -771,6 +771,7 @@ void I_Quit(void)
 		ShowEndTxt(co);
 	}
 	fflush(stderr);
+	if (myargmalloc)
 		free(myargv); // Deallocate allocated memory
 	W_Shutdown();
 	exit(0);