Added testcase for the "deferred ops in unevaluated context" bug.

test/val/uneval.c

@@ -0,0 +1,46 @@
+/*
+  Copyright 2021, The cc65 Authors
+
+  This software is provided "as-is", without any express or implied
+  warranty. In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications; and, to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated, but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+
+/*
+  Test of deferred operations in unevaluated context resulted from 'sizeof' and
+  short-circuited code-paths in AND, OR and tenary operations.
+
+  https://github.com/cc65/cc65/issues/1406
+*/
+
+#include <stdio.h>
+
+int main(void)
+{
+    int i = 0;
+    int j = 0;
+
+    sizeof(i++ | j--);
+    0 && (i++ | j--);
+    1 || (i++ | j--);
+    0 ? i++ | j-- : 0;
+    1 ? 0 : i++ | j--;
+
+    if (i != 0 || j != 0) {
+        printf("i = %d, j = %d\n", i, j);
+        printf("Failures: %d\n", i - j);
+    }
+    return i - j;
+}