diff --git a/glslang/MachineIndependent/Versions.h b/glslang/MachineIndependent/Versions.h
index e8cebeb..22a9ed7 100644
--- a/glslang/MachineIndependent/Versions.h
+++ b/glslang/MachineIndependent/Versions.h
@@ -52,7 +52,7 @@
 // Don't maintain an ordinal set of enums (0,1,2,3...) to avoid all possible
 // defects from mixing the two different forms.
 //
-typedef enum {
+typedef enum : unsigned {
     EBadProfile           = 0,
     ENoProfile            = (1 << 0), // only for desktop, before profiles showed up
     ECoreProfile          = (1 << 1),
diff --git a/glslang/Public/ShaderLang.h b/glslang/Public/ShaderLang.h
index acb2a07..ad98494 100755
--- a/glslang/Public/ShaderLang.h
+++ b/glslang/Public/ShaderLang.h
@@ -109,7 +109,7 @@
     LAST_ELEMENT_MARKER(EShLangCount),
 } EShLanguage;         // would be better as stage, but this is ancient now
 
-typedef enum {
+typedef enum : unsigned {
     EShLangVertexMask         = (1 << EShLangVertex),
     EShLangTessControlMask    = (1 << EShLangTessControl),
     EShLangTessEvaluationMask = (1 << EShLangTessEvaluation),
@@ -240,7 +240,7 @@
 //
 // Message choices for what errors and warnings are given.
 //
-enum EShMessages {
+enum EShMessages : unsigned {
     EShMsgDefault          = 0,         // default is to give all required errors and extra warnings
     EShMsgRelaxedErrors    = (1 << 0),  // be liberal in accepting input
     EShMsgSuppressWarnings = (1 << 1),  // suppress all warnings, except those required by the specification