[PATCH] volatile declarations (was Re: 'while do done' hangs interactive zsh)

[Bart Schaefer <schaefer@brasslantern.com>]

[-- Attachment #1: Type: text/plain, Size: 236 bytes --]

On Sun, May 16, 2021 at 1:34 PM Peter Stephenson
<p.w.stephenson@ntlworld.com> wrote:
>
> I think we lost the pre-ISO world some time ago now.  I can't believe
> "volatile" is a problem.

OK, see attached.  I hope I haven't missed any.

[-- Attachment #2: volatile.txt --]
[-- Type: text/plain, Size: 4906 bytes --]

diff --git a/Src/builtin.c b/Src/builtin.c
index a29eb49e4..a16fddcb7 100644
--- a/Src/builtin.c
+++ b/Src/builtin.c
@@ -5635,13 +5635,16 @@ bin_getopts(UNUSED(char *name), char **argv, UNUSED(Options ops), UNUSED(int fun
  */
 
 /**/
-mod_export int
-exit_pending;
+mod_export volatile int exit_pending;
 
 /* Shell level at which we exit if exit_pending */
 /**/
-mod_export int
-exit_level;
+mod_export volatile int exit_level;
+
+/* we have printed a 'you have stopped (running) jobs.' message */
+
+/**/
+mod_export volatile int stopmsg;
 
 /* break, bye, continue, exit, logout, return -- most of these take   *
  * one numeric argument, and the other (logout) is related to return. *
@@ -5733,11 +5736,6 @@ bin_break(char *name, char **argv, UNUSED(Options ops), int func)
     return 0;
 }
 
-/* we have printed a 'you have stopped (running) jobs.' message */
-
-/**/
-mod_export int stopmsg;
-
 /* check to see if user has jobs running/stopped */
 
 /**/
diff --git a/Src/exec.c b/Src/exec.c
index 6f09e0d9f..49ff88b80 100644
--- a/Src/exec.c
+++ b/Src/exec.c
@@ -84,7 +84,7 @@ int nohistsave;
 /* error flag: bits from enum errflag_bits */
 
 /**/
-mod_export int errflag;
+mod_export volatile int errflag;
 
 /*
  * State of trap return value.  Value is from enum trap_state.
@@ -122,7 +122,7 @@ int subsh;
 /* != 0 if we have a return pending */
 
 /**/
-mod_export int retflag;
+mod_export volatile int retflag;
 
 /**/
 long lastval2;
@@ -1268,7 +1268,9 @@ execsimple(Estate state)
     } else {
 	int q = queue_signal_level();
 	dont_queue_signals();
-	if (code == WC_FUNCDEF)
+	if (errflag)
+	    lv = errflag;
+	else if (code == WC_FUNCDEF)
 	    lv = execfuncdef(state, NULL);
 	else
 	    lv = (execfuncs[code - WC_CURSH])(state, 0);
diff --git a/Src/loop.c b/Src/loop.c
index aa733a2cb..db5b3e097 100644
--- a/Src/loop.c
+++ b/Src/loop.c
@@ -43,7 +43,7 @@ mod_export int contflag;
 /* # of break levels */
  
 /**/
-mod_export int breaks;
+mod_export volatile int breaks;
 
 /**/
 int
diff --git a/Src/makepro.awk b/Src/makepro.awk
index 226d3f96b..f69660531 100644
--- a/Src/makepro.awk
+++ b/Src/makepro.awk
@@ -79,7 +79,7 @@ BEGIN {
 	    break
     }
     sub(/^ */, "", line)
-    match(line, /^((const|enum|mod_export|static|struct|union) +)*([_0-9A-Za-z]+ +|((char|double|float|int|long|short|unsigned|void) +)+)((const|static) +)*/)
+    match(line, /^((const|enum|mod_export|static|struct|union|volatile) +)*([_0-9A-Za-z]+ +|((char|double|float|int|long|short|unsigned|void) +)+)((const|static) +)*/)
     dtype = substr(line, 1, RLENGTH)
     sub(/ *$/, "", dtype)
     if(" " dtype " " ~ / static /)
diff --git a/Src/params.c b/Src/params.c
index 20dfb5b5f..4f6b361f9 100644
--- a/Src/params.c
+++ b/Src/params.c
@@ -98,8 +98,10 @@ char *ifs,		/* $IFS         */
      *pwd;		/* $PWD         */
 
 /**/
-mod_export
-zlong lastval,		/* $?           */
+mod_export volatile zlong
+     lastval;		/* $?           */
+/**/
+mod_export zlong
      mypid,		/* $$           */
      lastpid,		/* $!           */
      zterm_columns,	/* $COLUMNS     */
diff --git a/Src/signals.c b/Src/signals.c
index 4adf03202..2c540f38f 100644
--- a/Src/signals.c
+++ b/Src/signals.c
@@ -53,7 +53,7 @@ mod_export Eprog siglists[VSIGCOUNT];
 /* Total count of trapped signals */
 
 /**/
-mod_export int nsigtrapped;
+mod_export volatile int nsigtrapped;
 
 /* Running an exit trap? */
 
@@ -72,20 +72,20 @@ static int exit_trap_posix;
 /* Variables used by signal queueing */
 
 /**/
-mod_export int queueing_enabled, queue_front, queue_rear;
+mod_export volatile int queueing_enabled, queue_front, queue_rear;
 /**/
 mod_export int signal_queue[MAX_QUEUE_SIZE];
 /**/
 mod_export sigset_t signal_mask_queue[MAX_QUEUE_SIZE];
 #ifdef DEBUG
 /**/
-mod_export int queue_in;
+mod_export volatile int queue_in;
 #endif
 
 /* Variables used by trap queueing */
 
 /**/
-mod_export int trap_queueing_enabled, trap_queue_front, trap_queue_rear;
+mod_export volatile int trap_queueing_enabled, trap_queue_front, trap_queue_rear;
 /**/
 mod_export int trap_queue[MAX_QUEUE_SIZE];
 
@@ -672,9 +672,9 @@ zhandler(int sig)
 	    if ((isset(PRIVILEGED) || isset(RESTRICTED)) &&
 		isset(INTERACTIVE) && (noerrexit & NOERREXIT_SIGNAL))
 		zexit(SIGINT, ZEXIT_SIGNAL);
+            errflag |= ERRFLAG_INT;
             if (list_pipe || chline || simple_pline) {
                 breaks = loops;
-                errflag |= ERRFLAG_INT;
 		inerrflush();
 		check_cursh_sig(SIGINT);
             }
@@ -1266,19 +1266,19 @@ unqueue_traps(void)
 
 /* Are we already executing a trap? */
 /**/
-int intrap;
+volatile int intrap;
 
 /* Is the current trap a function? */
 
 /**/
-int trapisfunc;
+volatile int trapisfunc;
 
 /*
  * If the current trap is not a function, at what function depth
  * did the trap get called?
  */
 /**/
-int traplocallevel;
+volatile int traplocallevel;
 
 /*
  * sig is the signal number.