Added tests for diagnostics in unevaluated context.

test/misc/Makefile

@@ -64,12 +64,6 @@ $(WORKDIR)/int-static-1888.$1.$2.prg: int-static-1888.c | $(WORKDIR)
 	$(if $(QUIET),echo misc/int-static-1888.$1.$2.prg)
 	$(NOT) $(CC65) -t sim$2 -$1 -o $$@ $$< $(NULLERR)
 
-# should compile, but gives an error
-$(WORKDIR)/bug1768.$1.$2.prg: bug1768.c | $(WORKDIR)
-	@echo "FIXME: " $$@ "currently does not compile."
-	$(if $(QUIET),echo misc/bug1768.$1.$2.prg)
-	$(NOT) $(CC65) -t sim$2 -$1 -o $$@ $$< $(NULLERR)
-
 # should compile, but gives an error
 $(WORKDIR)/bug760.$1.$2.prg: bug760.c | $(WORKDIR)
 	@echo "FIXME: " $$@ "currently does not compile."
@@ -138,6 +132,14 @@ $(WORKDIR)/bug1265.$1.$2.prg: bug1265.c | $(WORKDIR)
 	$(LD65) -t sim$2 -o $$@ $$(@:.prg=.o) sim$2.lib $(NULLERR)
 	$(SIM65) $(SIM65FLAGS) $$@ $(NULLOUT) $(NULLERR)
 
+# this one requires -Werror
+$(WORKDIR)/bug1768.$1.$2.prg: bug1768.c | $(WORKDIR)
+	$(if $(QUIET),echo misc/bug1768.$1.$2.prg)
+	$(CC65) -Werror -t sim$2 -$1 -o $$(@:.prg=.s) $$< $(NULLERR)
+	$(CA65) -t sim$2 -o $$(@:.prg=.o) $$(@:.prg=.s) $(NULLERR)
+	$(LD65) -t sim$2 -o $$@ $$(@:.prg=.o) sim$2.lib $(NULLERR)
+	$(SIM65) $(SIM65FLAGS) $$@ $(NULLOUT) $(NULLERR)
+
 # should compile, but then hangs in an endless loop
 $(WORKDIR)/endless.$1.$2.prg: endless.c | $(WORKDIR)
 	$(if $(QUIET),echo misc/endless.$1.$2.prg)

test/misc/bug1768.c

@@ -1,14 +1,147 @@
+/*
+  Copyright 2021-2022, The cc65 Authors
 
-#include <stdlib.h>
+  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.
 
-int a = 1 || (8 / 0);
+  Permission is granted to anyone to use this software for any purpose,
-int b = 0 && (8 % 0);
+  including commercial applications; and, to alter it and redistribute it
-int c = 1 ? 42 : (0 % 0);
+  freely, subject to the following restrictions:
-int d = 1 || a / 0;
-int e = 0 && b % 0;
-int f = 1 ? 42 : (a %= 0, b /= 0);
 
+  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 operations in unevaluated context resulted from 'sizeof' and
+  short-circuited code-paths in AND, OR and conditional operations.
+
+  See also:
+  https://github.com/cc65/cc65/issues/1768#issuecomment-1175221466
+*/
+
+#include <stdio.h>
+
+static int failures;
+
+#define TEST(EXPR)\
+    {\
+        int acc = 0;\
+        acc += sizeof((EXPR), 0);\
+        acc += (0 && (EXPR));\
+        acc += (1 || (EXPR));\
+        acc += (0 ? (EXPR) : 0);\
+        acc += (1 ? 0 : (EXPR));\
+        if (acc == 0) {\
+            printf("acc = %d\n", acc);\
+            ++failures;\
+        }\
+    }
+
+/* Division by zero/modulo with zero */
+void test_1(void)
+{
+    int i;
+    int j;
+    TEST((i / 0) | (j % 0))
+}
+
+/* Division by zero/modulo with zero */
+void test_2(void)
+{
+    int i;
+    int j;
+    TEST((i /= 0) | (j %= 0))
+}
+
+/* Shift by too wide counts */
+void test_3(void)
+{
+    int i;
+    int j;
+    TEST((i << 32) | (j >> 32))
+}
+
+/* Shift by too wide counts */
+void test_4(void)
+{
+    int i;
+    int j;
+    TEST((i <<= 32) | (j >>= 32))
+}
+
+/* Shift by negative counts */
+void test_5(void)
+{
+    int i;
+    int j;
+    TEST((i << -1) | (j >> -1))
+}
+
+/* Shift by negative counts */
+void test_6(void)
+{
+    int i;
+    int j;
+    TEST((i <<= -1) | (j >>= -1))
+}
+
+/* Shift bit-fields */
+void test_7(void)
+{
+    struct S {
+        long i : 24;    /* Will be promoted to 32-bit integer in calculation */
+        long j : 8;     /* Will be promoted to 16-bit integer in calculation */
+    } s;
+    long k;
+
+    s.i = 1;
+    printf("%u\n", sizeof(s.i << 24));
+    s.i = 2;
+    k = s.i << 16;
+    if (k != 0x00020000L) {
+        printf("k = %ld, expected: %ld\n", k, 0x00020000L);
+    }
+    TEST(s.j >> 16)
+}
+
+/* Shift bit-fields */
+void test_8(void)
+{
+    struct S {
+        long i : 24;    /* Will be promoted to 32-bit integer in calculation */
+        long j : 8;     /* Will be promoted to 16-bit integer in calculation */
+    } s;
+    long k;
+
+    s.i = 3;
+    printf("%u\n", sizeof(s.i << 24));
+    s.i = 4;
+    k = s.i <<= 16;
+    if (k != 0x00040000L) {
+        printf("k = %ld, expected: %ld\n", k, 0x00040000L);
+    }
+    TEST(s.j >>= 8)
+}
+
+/* Do all tests */
 int main(void)
 {
-    return EXIT_SUCCESS;
+    test_1();
+    test_2();
+    test_3();
+    test_4();
+    test_5();
+    test_6();
+    test_7();
+    test_8();
+
+    printf("Failures: %d\n", failures);
+    return failures;
 }