32479: POSIXTRAPS and implicit return values.

With POSIXTRAPS never propagate implicit return value.
In any case if not forcing a return value don't use lastval
from within the trap, use the one from the surrounding code.

2 files changed, 17 insertions, 2 deletions

diff --git a/Src/builtin.c b/Src/builtin.c
index 9bcbcf707..0cc54b7bb 100644
--- a/Src/builtin.c
+++ b/Src/builtin.c
@@ -4688,9 +4688,10 @@ exit_pending;
 int
 bin_break(char *name, char **argv, UNUSED(Options ops), int func)
 {
-    int num = lastval, nump = 0;
+    int num = lastval, nump = 0, implicit;
 
     /* handle one optional numeric argument */
+    implicit = !*argv;
     if (*argv) {
 	num = mathevali(*argv++);
 	nump = 1;
@@ -4721,7 +4722,13 @@ bin_break(char *name, char **argv, UNUSED(Options ops), int func)
 	    retflag = 1;
 	    breaks = loops;
 	    lastval = num;
-	    if (trap_state == TRAP_STATE_PRIMED && trap_return == -2) {
+	    if (trap_state == TRAP_STATE_PRIMED && trap_return == -2
+		/*
+		 * With POSIX, "return" on its own in a trap doesn't
+		 * update $? --- we keep the status from before the
+		 * trap.
+		 */
+		&& !(isset(POSIXTRAPS) && implicit)) {
 		trap_state = TRAP_STATE_FORCE_RETURN;
 		trap_return = lastval;
 	    }
diff --git a/Src/signals.c b/Src/signals.c
index c8f5fbcca..a6eb8038b 100644
--- a/Src/signals.c
+++ b/Src/signals.c
@@ -1155,6 +1155,7 @@ dotrapargs(int sig, int *sigtr, void *sigfn)
     char *name, num[4];
     int obreaks = breaks;
     int oretflag = retflag;
+    int olastval = lastval;
     int isfunc;
     int traperr, new_trap_state, new_trap_return;
 
@@ -1261,6 +1262,13 @@ dotrapargs(int sig, int *sigtr, void *sigfn)
     } else {
 	if (traperr && !EMULATION(EMULATE_SH))
 	    lastval = 1;
+	else {
+	    /*
+	     * With no explicit forced return, we keep the
+	     * lastval from before the trap ran.
+	     */
+	    lastval = olastval;
+	}
 	if (try_tryflag)
 	    errflag = traperr;
 	breaks += obreaks;