diff --git a/Test/baseResults/cppComplexExpr.vert.out b/Test/baseResults/cppComplexExpr.vert.out
index 0cda42e7bbbab70b7460f4d7683477b82e56af88..100123ab620f6ab0251ca9a3fa6f4bb479cb93c4 100644
--- a/Test/baseResults/cppComplexExpr.vert.out
+++ b/Test/baseResults/cppComplexExpr.vert.out
@@ -34,8 +34,16 @@ ERROR: 0:153: 'preprocessor evaluation' : undefined macro in expression not allo
 ERROR: 0:156: 'preprocessor evaluation' : undefined macro in expression not allowed in es profile UNDEF2
 ERROR: 0:159: 'preprocessor evaluation' : undefined macro in expression not allowed in es profile UNDEF2
 ERROR: 0:3000: '#error' : line of this error should be 3000  
+ERROR: 0:3002: '#define' : predefined names can't be (un)defined: __LINE__
+ERROR: 0:3003: '#define' : predefined names can't be (un)defined: __FILE__
+ERROR: 0:3004: '#define' : predefined names can't be (un)defined: __VERSION__
+ERROR: 0:3005: '#define' : names beginning with "GL_" can't be (un)defined: GL_SOME_EXTENSION
+ERROR: 0:3006: '#undef' : predefined names can't be (un)defined: __LINE__
+ERROR: 0:3007: '#undef' : predefined names can't be (un)defined: __FILE__
+ERROR: 0:3008: '#undef' : predefined names can't be (un)defined: __VERSION__
+ERROR: 0:3009: '#undef' : names beginning with "GL_" can't be (un)defined: GL_SOME_EXTENSION
 ERROR: 0:10001: '' : missing #endif 
-ERROR: 36 compilation errors.  No code generated.
+ERROR: 44 compilation errors.  No code generated.
 
 
 Shader version: 300
diff --git a/Test/baseResults/cppSimple.vert.out b/Test/baseResults/cppSimple.vert.out
index cbe3c5279eb7bf375c192a25e58b986958463ddc..2e6a9b4a5d99bdb3edad3b75c57d1a11d3b263b6 100644
--- a/Test/baseResults/cppSimple.vert.out
+++ b/Test/baseResults/cppSimple.vert.out
@@ -25,8 +25,8 @@ ERROR: 0:136: 'length' : no matching overloaded function found
 ERROR: 0:136: '=' :  cannot convert from 'const float' to 'int'
 ERROR: 0:138: ''' : character literals not supported 
 ERROR: 0:138: ''' : character literals not supported 
-ERROR: 0:141: '#define' : names beginning with "GL_" can't be defined: GL_
-ERROR: 0:142: '#define' : names beginning with "GL_" can't be defined: GL_Macro
+ERROR: 0:141: '#define' : names beginning with "GL_" can't be (un)defined: GL_
+ERROR: 0:142: '#define' : names beginning with "GL_" can't be (un)defined: GL_Macro
 WARNING: 0:143: '#define' : names containing consecutive underscores are reserved: __M
 WARNING: 0:144: '#define' : names containing consecutive underscores are reserved: M__
 WARNING: 0:145: '#define' : names containing consecutive underscores are reserved: ABC__DE
@@ -43,7 +43,7 @@ ERROR: 0:185: '#define' : Macro redefined; different substitutions: m7
 ERROR: 0:192: '#define' : Macro redefined; different substitutions: m8
 ERROR: 0:196: '#define' : Macro redefined; different argument names: m9
 WARNING: 0:204: '#undef' : names containing consecutive underscores are reserved: __VERSION__
-ERROR: 0:205: '#undef' : names beginning with "GL_" can't be defined: GL_ARB_texture_rectangle
+ERROR: 0:205: '#undef' : names beginning with "GL_" can't be (un)defined: GL_ARB_texture_rectangle
 ERROR: 0:210: '#' : invalid directive 
 ERROR: 0:211: '#' : invalid directive 
 ERROR: 0:212: '#' : invalid directive 
diff --git a/Test/cppComplexExpr.vert b/Test/cppComplexExpr.vert
index fe01cd59453e9bf98a034eac556da2ce7463fff5..3f15b5ef2abdf7ca221e757077badd788380402f 100644
--- a/Test/cppComplexExpr.vert
+++ b/Test/cppComplexExpr.vert
@@ -161,6 +161,15 @@ float c = foobar(1.1, 2.2
 
 #line 3000
 #error line of this error should be 3000
+    
+#define __LINE__ 30
+#define __FILE__
+#define __VERSION__
+#define GL_SOME_EXTENSION
+#undef __LINE__
+#undef __FILE__
+#undef __VERSION__
+#undef GL_SOME_EXTENSION
 
 #line 10000
 #if 0
diff --git a/glslang/MachineIndependent/ParseHelper.cpp b/glslang/MachineIndependent/ParseHelper.cpp
index 0837553a8eb6a6b646084a9e43038cd26e275d0e..e150c507c6c95758bc510b8c991d4e26ec8f5322 100644
--- a/glslang/MachineIndependent/ParseHelper.cpp
+++ b/glslang/MachineIndependent/ParseHelper.cpp
@@ -1783,9 +1783,16 @@ void TParseContext::reservedPpErrorCheck(TSourceLoc loc, const char* identifier,
     // single underscore) are also reserved, and defining such a name results in a
     // compile-time error."
     if (strncmp(identifier, "GL_", 3) == 0)
-        error(loc, "names beginning with \"GL_\" can't be defined:", op,  identifier);
-    else if (strstr(identifier, "__") != 0)
-        warn(loc, "names containing consecutive underscores are reserved:", op, identifier);
+        error(loc, "names beginning with \"GL_\" can't be (un)defined:", op,  identifier);
+    else if (strstr(identifier, "__") != 0) {
+        if (profile == EEsProfile && version >= 300 &&
+            (strcmp(identifier, "__LINE__") == 0 ||
+             strcmp(identifier, "__FILE__") == 0 ||
+             strcmp(identifier, "__VERSION__") == 0))
+            error(loc, "predefined names can't be (un)defined:", op,  identifier);
+        else
+            warn(loc, "names containing consecutive underscores are reserved:", op, identifier);
+    }
 }
 
 //