Add ability to treat keywords as identifiers in versions that had not yet reserved the keyword.

Test/120.frag

 #version 120
 
-lowp vec3 a;
-mediump float b;
-highp int c;
+float lowp;
+float mediump;
+float highp;
 
-precision highp float;
+float precision;
 
 in vec4 i;
 out vec4 o;

Test/specExamples.frag

@@ -6,11 +6,11 @@ int  a = 0xffffffff;  // 32 bits, a gets the value -1
 //int  b = 0xffffffffU; // ERROR: can't convert uint to int
 uint c = 0xffffffff;  // 32 bits, c gets the value 0xFFFFFFFF
 //uint d = 0xffffffffU; // 32 bits, d gets the value 0xFFFFFFFF
-int  e = -1;          // the literal is “1”, then negation is performed,
+int  e = -1;          // the literal is "1", then negation is performed,
                       //   and the resulting non-literal 32-bit signed 
                       //   bit pattern of 0xFFFFFFFF is assigned, giving e 
                       //   the value of -1.
-//uint f = -1u;         // the literal is “1u”, then negation is performed,
+//uint f = -1u;         // the literal is "1u", then negation is performed,
                       //   and the resulting non-literal 32-bit unsigned 
                       //   bit pattern of 0xFFFFFFFF is assigned, giving f 
                       //   the value of 0xFFFFFFFF.
@@ -58,20 +58,20 @@ light lights[];
 const int numLights = 2;
 light lights[numLights];
 
-in vec3 normal;
+in vec3 normal;
 centroid in vec2 TexCoord;
 invariant centroid in vec4 Color;
 noperspective in float temperature;
 flat in vec3 myColor;
 noperspective centroid in vec2 myTexCoord;
 
-uniform vec4 lightPosition;
+uniform vec4 lightPosition;
 uniform vec3 color = vec3(0.7, 0.7, 0.2);  // value assigned at link time
 
-in Material {
-    smooth in vec4 Color1; // legal, input inside in block
-    smooth vec4 Color2;    // legal, 'in' inherited from 'in Material'
-    vec2 TexCoord;         // legal, TexCoord is an input
+in Material {
+    smooth in vec4 Color1; // legal, input inside in block
+    smooth vec4 Color2;    // legal, 'in' inherited from 'in Material'
+    vec2 TexCoord;         // legal, TexCoord is an input
     uniform float Atten;   // illegal, mismatched  storage qualifier
 
 };
@@ -80,8 +80,8 @@ in Light {
     vec4 LightPos;
     vec3 LightColor;
 };
-in ColoredTexture {
-    vec4 Color;
+in ColoredTexture {
+    vec4 Color;
     vec2 TexCoord;        
 } Material;            // instance name
 vec3 Color;            // different Color than Material.Color
@@ -104,8 +104,8 @@ layout(location = 3, index = 1) out vec4 factor;
 layout(location = 2) out vec4 colors[3];
 
 layout (depth_greater) out float gl_FragDepth;
-
-// redeclaration that changes nothing is allowed
+
+// redeclaration that changes nothing is allowed
 out float gl_FragDepth;
 
 // assume it may be modified in any way
@@ -120,7 +120,7 @@ layout (depth_less) out float gl_FragDepth;
 // assume it will not be modified
 layout (depth_unchanged) out float gl_FragDepth;
 
-in vec4 gl_Color;             // predeclared by the fragment language
+in vec4 gl_Color;             // predeclared by the fragment language
 flat  in vec4 gl_Color;       // redeclared by user to be flat
 
 

glslang/MachineIndependent/glslang.y

@@ -73,6 +73,7 @@ Jutta Degener, 1995
 #endif
 
 %}
+
 %union {
     struct {
         TSourceLoc line;
@@ -1664,6 +1665,7 @@ storage_qualifier
 
         parseContext.checkDeprecated($1.line, ENoProfile, 140, "attribute");
         parseContext.requireNotRemoved($1.line, ECoreProfile, 420, "attribute");
+        parseContext.requireNotRemoved($1.line, EEsProfile, 300, "attribute");
 
         if (parseContext.globalErrorCheck($1.line, parseContext.symbolTable.atGlobalLevel(), "attribute"))
             parseContext.recover();
@@ -1674,6 +1676,7 @@ storage_qualifier
     | VARYING {
         parseContext.checkDeprecated($1.line, ENoProfile, 140, "varying");
         parseContext.requireNotRemoved($1.line, ECoreProfile, 420, "varying");
+        parseContext.requireNotRemoved($1.line, EEsProfile, 300, "varying");
         
         if (parseContext.globalErrorCheck($1.line, parseContext.symbolTable.atGlobalLevel(), "varying"))
             parseContext.recover();