Re: [BUG] program flow corruption involving dot script and 'until' loop

[Peter Stephenson <p.w.stephenson@ntlworld.com>]

On Fri, 2019-05-03 at 18:20 +0100, Martijn Dekker wrote:
> Looks like the 'return' in the dot script causes zsh to just give up on 
> the program altogether.

diff --git a/Src/loop.c b/Src/loop.c
index 1013aeb50..3fa7006aa 100644
--- a/Src/loop.c
+++ b/Src/loop.c
@@ -425,7 +425,7 @@ execwhile(Estate state, UNUSED(int do_exec))
         breaks--;
 
         simple_pline = old_simple_pline;
-    } else
+    } else {
         for (;;) {
             state->pc = loop;
             noerrexit = NOERREXIT_EXIT | NOERREXIT_RETURN;
@@ -445,8 +445,11 @@ execwhile(Estate state, UNUSED(int do_exec))
 		    lastval = oldval;
                 break;
             }
-            if (retflag)
+            if (retflag) {
+		if (breaks)
+		    breaks--;
                 break;
+	    }
 
 	    /* In case the loop body is also a functional no-op,
 	     * make sure signal handlers recognize ^C as above. */
@@ -470,6 +473,7 @@ execwhile(Estate state, UNUSED(int do_exec))
             freeheap();
             oldval = lastval;
         }
+    }
     cmdpop();
     popheap();
     loops--;
diff --git a/Test/A01grammar.ztst b/Test/A01grammar.ztst
index 339ce7494..1ed3cb6b7 100644
--- a/Test/A01grammar.ztst
+++ b/Test/A01grammar.ztst
@@ -640,6 +640,16 @@
 >1
 >0
 
+  echo 'echo dot
+  until return 42; do
+    :
+  done' >until_dot
+  . ./until_dot
+  echo After dot
+0:return in positive until test in dot file does not cause excess breaks
+>dot
+>After dot
+
   echo 'echo $?' >dot_status
   false
   . ./dot_status