HLSL: Handle const with no initializer. Fixes issue #651.

hlsl/hlslParseHelper.cpp

@@ -3892,6 +3892,23 @@ void HlslParseContext::updateImplicitArraySize(const TSourceLoc& loc, TIntermNod
     symbol->getWritableType().setImplicitArraySize(index + 1);
 }
 
+//
+// Enforce non-initializer type/qualifier rules.
+//
+void HlslParseContext::fixConstInit(const TSourceLoc& loc, TString& identifier, TType& type, TIntermTyped*& initializer)
+{
+    //
+    // Make the qualifier make sense, given that there is an initializer.
+    //
+    if (initializer == nullptr) {
+        if (type.getQualifier().storage == EvqConst ||
+            type.getQualifier().storage == EvqConstReadOnly) {
+            initializer = intermediate.makeAggregate(loc);
+            warn(loc, "variable with qualifier 'const' not initialized; zero initializing", identifier.c_str(), "");
+        }
+    }
+}
+
 //
 // See if the identifier is a built-in symbol that can be redeclared, and if so,
 // copy the symbol table's read-only built-in variable to the current
@@ -4736,6 +4753,9 @@ TIntermNode* HlslParseContext::declareVariable(const TSourceLoc& loc, TString& i
     if (voidErrorCheck(loc, identifier, type.getBasicType()))
         return nullptr;
 
+    // make const and initialization consistent
+    fixConstInit(loc, identifier, type, initializer);
+
     // Check for redeclaration of built-ins and/or attempting to declare a reserved name
     TSymbol* symbol = nullptr;
 

hlsl/hlslParseHelper.h

@@ -183,6 +183,7 @@ protected:
         int                 nextBinding; // next binding to use.
     };
 
+    void fixConstInit(const TSourceLoc&, TString& identifier, TType& type, TIntermTyped*& initializer);
     void inheritGlobalDefaults(TQualifier& dst) const;
     TVariable* makeInternalVariable(const char* name, const TType&) const;
     TVariable* declareNonArray(const TSourceLoc&, TString& identifier, TType&, bool track);