Fix another problem with undefined macros needing to evaluate to 0 within a preprocessor expression, but not outside a preprocessor expression.

git-svn-id: https://cvs.khronos.org/svn/repos/ogl/trunk/ecosystem/public/sdk/tools/glslang@21815 e7fa87d3-cd2b-0410-9028-fcbf551c1848

Test/cppSimple.vert

@@ -68,3 +68,55 @@ sum += 0.05;
 // sum should be 987600301.7
     gl_Position = vec4(sum);
 }
+
+#define A 0
+#define B 0
+#define C 0
+
+#if (A == B) || (A == C)
+#error good1
+#endif
+
+#if A == B || (A == C)
+#error good2
+#endif
+
+#if (A == B || (A == C))
+#error good3
+#endif
+
+#if (AA == BB) || (AA == CC)
+#error good4
+#endif
+
+#if AA == BB || (AA == CC)
+#error good5
+#endif
+
+#if ((AA == BB || (AA == CC)))
+#error good6
+#endif
+
+#if (A == B || (A == C)
+#error bad1
+#endif
+
+#if A == B || A == C)
+#error bad2
+#endif
+
+#if (A == B || (A == C)
+#error bad3
+#endif
+
+#if AA == BB) || (AA == CC)
+#error bad4
+#endif
+
+#if AA == BB || (AA == CC
+#error bad5
+#endif
+
+#if ((AA == BB || (AA == CC))))
+#error bad6
+#endif