Make do_chmod() report an error with -E.

syscall.c

@@ -34,6 +34,7 @@ extern int am_root;
 extern int read_only;
 extern int list_only;
 extern int preserve_perms;
+extern int preserve_executability;
 
 #define RETURN_ERROR_IF(x,e) \
 	do { \
@@ -167,7 +168,7 @@ int do_chmod(const char *path, mode_t mode)
 #endif
 	} else
 		code = chmod(path, mode & CHMOD_BITS);
-	if (code != 0 && preserve_perms)
+	if (code != 0 && (preserve_perms || preserve_executability))
 	    return code;
 	return 0;
 }

t_unsafe.c

@@ -29,6 +29,7 @@ int read_only = 0;
 int list_only = 0;
 int verbose = 0;
 int preserve_perms = 0;
+int preserve_executability = 0;
 
 int
 main(int argc, char **argv)

tls.c

@@ -46,6 +46,7 @@ int am_root = 0;
 int read_only = 1;
 int list_only = 0;
 int preserve_perms = 0;
+int preserve_executability = 0;
 
 #ifdef SUPPORT_XATTRS
 

trimslash.c

@@ -26,6 +26,7 @@ int am_root = 0;
 int read_only = 1;
 int list_only = 0;
 int preserve_perms = 0;
+int preserve_executability = 0;
 
 int
 main(int argc, char **argv)