[SjLj] Add test for when setjmp is within a loop (#16112)

Author: aheejin

tests/core/test_setjmp_within_loop.c

@@ -0,0 +1,32 @@
+#include <setjmp.h>
+#include <stdio.h>
+
+static jmp_buf buf;
+
+void a() { printf("a\n"); }
+void b() { printf("b\n"); }
+void c() { printf("c\n"); }
+int d() {
+  static int first = 1;
+  if (first) {
+    first = 0;
+    printf("d\n");
+    return 1;
+  }
+  return 0;
+}
+
+int n = 3;
+
+int main() {
+  while (n-- > 0) {
+    a();
+    if (setjmp(buf))
+      b();
+    else
+      c();
+  }
+  if (d())
+    longjmp(buf, 3);
+  return 0;
+}

tests/core/test_setjmp_within_loop.out

@@ -0,0 +1,8 @@
+a
+c
+a
+c
+a
+c
+d
+b

tests/test_core.py

@@ -1142,6 +1142,10 @@ def test_setjmp_many_2(self):
   def test_setjmp_noleak(self):
     self.do_runf(test_file('core/test_setjmp_noleak.c'), 'ok.')
 
+  @with_both_eh_sjlj
+  def test_setjmp_within_loop(self):
+    self.do_core_test('test_setjmp_within_loop.c')
+
   @with_both_eh_sjlj
   def test_exceptions(self):
     self.set_setting('EXCEPTION_DEBUG')