Fixed array subscript with a bit-field with patch by kugelfuhr.

test/val/bug2186.c

@@ -0,0 +1,39 @@
+/* Bug #2186 - Wrong array indexing when index comes from bit-field */
+
+#include <stdio.h>
+
+unsigned failures;
+
+typedef struct {
+    char flag : 1;
+    char index : 7;
+} weird_type;
+
+const char array[] = { '6', '5', '0', '2' };
+
+weird_type data;
+
+int main(void) {
+    data.flag = 1;
+
+    data.index = 0;
+    if (array[data.index] != array[0])
+    {
+        ++failures;
+        printf("Got '%c', expected '%c'\n", array[data.index], array[0]);
+    }
+
+    data.index = 1;
+    if (array[data.index] != array[1])
+    {
+        ++failures;
+        printf("Got '%c', expected '%c'\n", array[data.index], array[1]);
+    }
+
+    if (failures > 0)
+    {
+        printf("Failures: %u\n", failures);
+    }
+
+    return failures;
+}