diff --git a/glslang/Include/Types.h b/glslang/Include/Types.h
index 1ea9f253..6c2ded8e 100644
--- a/glslang/Include/Types.h
+++ b/glslang/Include/Types.h
@@ -1075,7 +1075,7 @@ public:
                                 qualifier.clear();
                                 qualifier.storage = q;
                                 qualifier.precision = p;
-                                assert(p >= 0 && p <= EpqHigh);
+                                assert(p >= EpqNone && p <= EpqHigh);
                             }
     // for turning a TPublicType into a TType, using a shallow copy
     explicit TType(const TPublicType& p) :
diff --git a/glslang/Include/revision.h b/glslang/Include/revision.h
index 3a929fd9..00ffc1bc 100644
--- a/glslang/Include/revision.h
+++ b/glslang/Include/revision.h
@@ -2,5 +2,5 @@
 // For the version, it uses the latest git tag followed by the number of commits.
 // For the date, it uses the current date (when then script is run).
 
-#define GLSLANG_REVISION "SPIRV99.1426"
-#define GLSLANG_DATE "23-Aug-2016"
+#define GLSLANG_REVISION "SPIRV99.1384"
+#define GLSLANG_DATE "03-Aug-2016"
diff --git a/glslang/MachineIndependent/ParseHelper.cpp b/glslang/MachineIndependent/ParseHelper.cpp
index 7211d4b0..822c361e 100644
--- a/glslang/MachineIndependent/ParseHelper.cpp
+++ b/glslang/MachineIndependent/ParseHelper.cpp
@@ -61,6 +61,43 @@ TParseContext::TParseContext(TSymbolTable& symbolTable, TIntermediate& interm, b
     // ensure we always have a linkage node, even if empty, to simplify tree topology algorithms
     linkage = new TIntermAggregate;
 
+    // decide whether precision qualifiers should be ignored or respected
+    obeyPrecisionQualifiers_ = profile == EEsProfile;
+    setPrecisionDefaults();
+
+    globalUniformDefaults.clear();
+    globalUniformDefaults.layoutMatrix = ElmColumnMajor;
+    globalUniformDefaults.layoutPacking = spvVersion.spv != 0 ? ElpStd140 : ElpShared;
+
+    globalBufferDefaults.clear();
+    globalBufferDefaults.layoutMatrix = ElmColumnMajor;
+    globalBufferDefaults.layoutPacking = spvVersion.spv != 0 ? ElpStd430 : ElpShared;
+
+    globalInputDefaults.clear();
+    globalOutputDefaults.clear();
+
+    // "Shaders in the transform 
+    // feedback capturing mode have an initial global default of
+    //     layout(xfb_buffer = 0) out;"
+    if (language == EShLangVertex ||
+        language == EShLangTessControl ||
+        language == EShLangTessEvaluation ||
+        language == EShLangGeometry)
+        globalOutputDefaults.layoutXfbBuffer = 0;
+
+    if (language == EShLangGeometry)
+        globalOutputDefaults.layoutStream = 0;
+}
+
+TParseContext::~TParseContext()
+{
+    delete [] atomicUintOffsets;
+}
+
+// Set up all default precisions as needed by the current environment.
+// Intended just as a TParseContext constructor helper.
+void TParseContext::setPrecisionDefaults()
+{
     // set all precision defaults to EpqNone, which is correct for all desktop types
     // and for ES types that don't have defaults (thus getting an error on use)
     for (int type = 0; type < EbtNumTypes; ++type)
@@ -70,7 +107,7 @@ TParseContext::TParseContext(TSymbolTable& symbolTable, TIntermediate& interm, b
         defaultSamplerPrecision[type] = EpqNone;
 
     // replace with real precision defaults for those that have them
-    if (profile == EEsProfile) {
+    if (obeyPrecisionQualifiers()) {
         TSampler sampler;
         sampler.set(EbtFloat, Esd2D);
         defaultSamplerPrecision[computeSamplerTypeIndex(sampler)] = EpqLow;
@@ -101,34 +138,6 @@ TParseContext::TParseContext(TSymbolTable& symbolTable, TIntermediate& interm, b
         defaultPrecision[EbtSampler] = EpqLow;
         defaultPrecision[EbtAtomicUint] = EpqHigh;
     }
-
-    globalUniformDefaults.clear();
-    globalUniformDefaults.layoutMatrix = ElmColumnMajor;
-    globalUniformDefaults.layoutPacking = spvVersion.spv != 0 ? ElpStd140 : ElpShared;
-
-    globalBufferDefaults.clear();
-    globalBufferDefaults.layoutMatrix = ElmColumnMajor;
-    globalBufferDefaults.layoutPacking = spvVersion.spv != 0 ? ElpStd430 : ElpShared;
-
-    globalInputDefaults.clear();
-    globalOutputDefaults.clear();
-
-    // "Shaders in the transform 
-    // feedback capturing mode have an initial global default of
-    //     layout(xfb_buffer = 0) out;"
-    if (language == EShLangVertex ||
-        language == EShLangTessControl ||
-        language == EShLangTessEvaluation ||
-        language == EShLangGeometry)
-        globalOutputDefaults.layoutXfbBuffer = 0;
-
-    if (language == EShLangGeometry)
-        globalOutputDefaults.layoutStream = 0;
-}
-
-TParseContext::~TParseContext()
-{
-    delete [] atomicUintOffsets;
 }
 
 void TParseContext::setLimits(const TBuiltInResource& r)
@@ -1223,7 +1232,9 @@ TIntermTyped* TParseContext::handleBuiltInFunctionCall(TSourceLoc loc, TIntermNo
     TIntermTyped *result = intermediate.addBuiltInFunctionCall(loc, function.getBuiltInOp(),
                                                                function.getParamCount() == 1,
                                                                &arguments, function.getType());
-    computeBuiltinPrecisions(*result, function);
+    if (obeyPrecisionQualifiers())
+        computeBuiltinPrecisions(*result, function);
+
     if (result == nullptr)  {
         error(arguments.getLoc(), " wrong operand type", "Internal Error",
                                   "built in unary operator function.  Type: %s",
@@ -1271,9 +1282,6 @@ void TParseContext::computeBuiltinPrecisions(TIntermTyped& node, const TFunction
     TPrecisionQualifier operationPrecision = EpqNone;
     TPrecisionQualifier resultPrecision = EpqNone;
 
-    if (profile != EEsProfile)
-        return;
-
     TIntermOperator* opNode = node.getAsOperator();
     if (opNode == nullptr)
         return;
@@ -2934,7 +2942,7 @@ void TParseContext::precisionQualifierCheck(const TSourceLoc& loc, TBasicType ba
 {
     // Built-in symbols are allowed some ambiguous precisions, to be pinned down
     // later by context.
-    if (profile != EEsProfile || parsingBuiltins)
+    if (! obeyPrecisionQualifiers() || parsingBuiltins)
         return;
 
     if (baseType == EbtAtomicUint && qualifier.precision != EpqNone && qualifier.precision != EpqHigh)
diff --git a/glslang/MachineIndependent/ParseHelper.h b/glslang/MachineIndependent/ParseHelper.h
index 544c3d30..0c64b570 100644
--- a/glslang/MachineIndependent/ParseHelper.h
+++ b/glslang/MachineIndependent/ParseHelper.h
@@ -80,7 +80,7 @@ public:
             symbolTable(symbolTable), tokensBeforeEOF(false),
             linkage(nullptr), scanContext(nullptr), ppContext(nullptr) { }
     virtual ~TParseContextBase() { }
-    
+
     virtual void setLimits(const TBuiltInResource&) = 0;
     
     EShLanguage getLanguage() const { return language; }
@@ -155,6 +155,9 @@ public:
                   bool forwardCompatible = false, EShMessages messages = EShMsgDefault);
     virtual ~TParseContext();
 
+    bool obeyPrecisionQualifiers() const { return obeyPrecisionQualifiers_; };
+    void setPrecisionDefaults();
+
     void setLimits(const TBuiltInResource&);
     bool parseShaderStrings(TPpContext&, TInputScanner& input, bool versionWillBeError = false);
     void parserError(const char* s);     // for bison's yyerror
@@ -351,6 +354,7 @@ protected:
     TIdSetType inductiveLoopIds;
     bool anyIndexLimits;
     TVector<TIntermTyped*> needsIndexLimitationChecking;
+    bool obeyPrecisionQualifiers_;
 
     //
     // Geometry shader input arrays:
diff --git a/glslang/MachineIndependent/glslang.y b/glslang/MachineIndependent/glslang.y
index 72bad947..aafe85c6 100644
--- a/glslang/MachineIndependent/glslang.y
+++ b/glslang/MachineIndependent/glslang.y
@@ -2206,19 +2206,19 @@ precision_qualifier
     : HIGH_PRECISION {
         parseContext.profileRequires($1.loc, ENoProfile, 130, 0, "highp precision qualifier");
         $$.init($1.loc, parseContext.symbolTable.atGlobalLevel());
-        if (parseContext.profile == EEsProfile)
+        if (parseContext.obeyPrecisionQualifiers())
             $$.qualifier.precision = EpqHigh;
     }
     | MEDIUM_PRECISION {
         parseContext.profileRequires($1.loc, ENoProfile, 130, 0, "mediump precision qualifier");
         $$.init($1.loc, parseContext.symbolTable.atGlobalLevel());
-        if (parseContext.profile == EEsProfile)
+        if (parseContext.obeyPrecisionQualifiers())
             $$.qualifier.precision = EpqMedium;
     }
     | LOW_PRECISION {
         parseContext.profileRequires($1.loc, ENoProfile, 130, 0, "lowp precision qualifier");
         $$.init($1.loc, parseContext.symbolTable.atGlobalLevel());
-        if (parseContext.profile == EEsProfile)
+        if (parseContext.obeyPrecisionQualifiers())
             $$.qualifier.precision = EpqLow;
     }
     ;
diff --git a/glslang/MachineIndependent/glslang_tab.cpp b/glslang/MachineIndependent/glslang_tab.cpp
index 0d1dc433..84f46dac 100644
--- a/glslang/MachineIndependent/glslang_tab.cpp
+++ b/glslang/MachineIndependent/glslang_tab.cpp
@@ -6667,7 +6667,7 @@ yyreduce:
     {
         parseContext.profileRequires((yyvsp[0].lex).loc, ENoProfile, 130, 0, "highp precision qualifier");
         (yyval.interm.type).init((yyvsp[0].lex).loc, parseContext.symbolTable.atGlobalLevel());
-        if (parseContext.profile == EEsProfile)
+        if (parseContext.obeyPrecisionQualifiers())
             (yyval.interm.type).qualifier.precision = EpqHigh;
     }
 #line 6674 "MachineIndependent/glslang_tab.cpp" /* yacc.c:1646  */
@@ -6678,7 +6678,7 @@ yyreduce:
     {
         parseContext.profileRequires((yyvsp[0].lex).loc, ENoProfile, 130, 0, "mediump precision qualifier");
         (yyval.interm.type).init((yyvsp[0].lex).loc, parseContext.symbolTable.atGlobalLevel());
-        if (parseContext.profile == EEsProfile)
+        if (parseContext.obeyPrecisionQualifiers())
             (yyval.interm.type).qualifier.precision = EpqMedium;
     }
 #line 6685 "MachineIndependent/glslang_tab.cpp" /* yacc.c:1646  */
@@ -6689,7 +6689,7 @@ yyreduce:
     {
         parseContext.profileRequires((yyvsp[0].lex).loc, ENoProfile, 130, 0, "lowp precision qualifier");
         (yyval.interm.type).init((yyvsp[0].lex).loc, parseContext.symbolTable.atGlobalLevel());
-        if (parseContext.profile == EEsProfile)
+        if (parseContext.obeyPrecisionQualifiers())
             (yyval.interm.type).qualifier.precision = EpqLow;
     }
 #line 6696 "MachineIndependent/glslang_tab.cpp" /* yacc.c:1646  */