diff --git a/include/dxc/dxcapi.h b/include/dxc/dxcapi.h
index da6f517fb..4d14ce1a2 100644
--- a/include/dxc/dxcapi.h
+++ b/include/dxc/dxcapi.h
@@ -125,7 +125,7 @@ IDxcLibrary : public IUnknown {
     LPCWSTR pFileName, _In_opt_ UINT32* codePage,
     _COM_Outptr_ IDxcBlobEncoding **pBlobEncoding) = 0;
   virtual HRESULT STDMETHODCALLTYPE CreateBlobWithEncodingFromPinned(
-    LPBYTE pText, UINT32 size, UINT32 codePage,
+    _In_bytecount_(size) LPCVOID pText, UINT32 size, UINT32 codePage,
     _COM_Outptr_ IDxcBlobEncoding **pBlobEncoding) = 0;
   virtual HRESULT STDMETHODCALLTYPE CreateBlobWithEncodingOnHeapCopy(
        _In_bytecount_(size) LPCVOID pText, UINT32 size, UINT32 codePage,
diff --git a/tools/clang/tools/dxcompiler/dxclibrary.cpp b/tools/clang/tools/dxcompiler/dxclibrary.cpp
index c9bbf825a..6175e7f53 100644
--- a/tools/clang/tools/dxcompiler/dxclibrary.cpp
+++ b/tools/clang/tools/dxcompiler/dxclibrary.cpp
@@ -77,7 +77,7 @@ public:
   }
 
   HRESULT STDMETHODCALLTYPE CreateBlobWithEncodingFromPinned(
-    LPBYTE pText, UINT32 size, UINT32 codePage,
+    _In_bytecount_(size) LPCVOID pText, UINT32 size, UINT32 codePage,
     _COM_Outptr_ IDxcBlobEncoding **pBlobEncoding) override {
     DxcThreadMalloc TM(m_pMalloc);
     return ::hlsl::DxcCreateBlobWithEncodingFromPinned(pText, size, codePage, pBlobEncoding);
diff --git a/tools/clang/unittests/HLSL/CompilerTest.cpp b/tools/clang/unittests/HLSL/CompilerTest.cpp
index 8864f7c56..247dab6d4 100644
--- a/tools/clang/unittests/HLSL/CompilerTest.cpp
+++ b/tools/clang/unittests/HLSL/CompilerTest.cpp
@@ -985,7 +985,7 @@ public:
                         UINT32 codePage, _Outptr_ IDxcBlobEncoding **ppBlob) {
     CComPtr<IDxcLibrary> library;
     IFT(m_dllSupport.CreateInstance(CLSID_DxcLibrary, &library));
-    IFT(library->CreateBlobWithEncodingFromPinned((LPBYTE)data, size, codePage,
+    IFT(library->CreateBlobWithEncodingFromPinned(data, size, codePage,
                                                   ppBlob));
   }
 
diff --git a/tools/clang/unittests/HLSL/ExecutionTest.cpp b/tools/clang/unittests/HLSL/ExecutionTest.cpp
index f7af854de..a61e15ba7 100644
--- a/tools/clang/unittests/HLSL/ExecutionTest.cpp
+++ b/tools/clang/unittests/HLSL/ExecutionTest.cpp
@@ -402,7 +402,7 @@ public:
     HRESULT resultCode;
     VERIFY_SUCCEEDED(m_support.CreateInstance(CLSID_DxcCompiler, &pCompiler));
     VERIFY_SUCCEEDED(m_support.CreateInstance(CLSID_DxcLibrary, &pLibrary));
-    VERIFY_SUCCEEDED(pLibrary->CreateBlobWithEncodingFromPinned((LPBYTE)pText, strlen(pText), CP_UTF8, &pTextBlob));
+    VERIFY_SUCCEEDED(pLibrary->CreateBlobWithEncodingFromPinned(pText, strlen(pText), CP_UTF8, &pTextBlob));
     VERIFY_SUCCEEDED(pCompiler->Compile(pTextBlob, L"hlsl.hlsl", pEntryPoint, pTargetProfile, nullptr, 0, nullptr, 0, nullptr, &pResult));
     VERIFY_SUCCEEDED(pResult->GetStatus(&resultCode));
     if (FAILED(resultCode)) {
diff --git a/tools/clang/unittests/HLSL/FileCheckerTest.cpp b/tools/clang/unittests/HLSL/FileCheckerTest.cpp
index a0b344e0f..63efaf35c 100644
--- a/tools/clang/unittests/HLSL/FileCheckerTest.cpp
+++ b/tools/clang/unittests/HLSL/FileCheckerTest.cpp
@@ -340,7 +340,7 @@ static string trim(string value) {
         CComPtr<IDxcAssembler> pAssembler;
         IFT(DllSupport->CreateInstance(CLSID_DxcAssembler, &pAssembler));
         IFT(pLibrary->CreateBlobWithEncodingFromPinned(
-            (LPBYTE)Prior->StdOut.c_str(), Prior->StdOut.size(), CP_UTF8,
+            Prior->StdOut.c_str(), Prior->StdOut.size(), CP_UTF8,
             &pSource));
       }
 
diff --git a/tools/clang/unittests/HLSL/RewriterTest.cpp b/tools/clang/unittests/HLSL/RewriterTest.cpp
index bf58bb661..461c3f7d5 100644
--- a/tools/clang/unittests/HLSL/RewriterTest.cpp
+++ b/tools/clang/unittests/HLSL/RewriterTest.cpp
@@ -109,7 +109,7 @@ public:
                         UINT32 codePage, _In_ IDxcBlobEncoding **ppBlob) {
     CComPtr<IDxcLibrary> library;
     IFT(m_dllSupport.CreateInstance(CLSID_DxcLibrary, &library));
-    IFT(library->CreateBlobWithEncodingFromPinned((LPBYTE)data, size, codePage,
+    IFT(library->CreateBlobWithEncodingFromPinned(data, size, codePage,
                                                   ppBlob));
   }
 
@@ -172,7 +172,7 @@ public:
       IFT(mapping.MapFile(file));
       CComPtr<IDxcLibrary> library;
       IFT(support.CreateInstance(CLSID_DxcLibrary, &library));
-      IFT(library->CreateBlobWithEncodingFromPinned((LPBYTE)mapping.GetData(),
+      IFT(library->CreateBlobWithEncodingFromPinned(mapping.GetData(),
                                                     mapping.GetMappingSize(),
                                                     CP_UTF8, &BlobEncoding));
     }
diff --git a/tools/clang/unittests/HLSL/ShaderOpTest.cpp b/tools/clang/unittests/HLSL/ShaderOpTest.cpp
index 5d748fe01..da5b40d69 100644
--- a/tools/clang/unittests/HLSL/ShaderOpTest.cpp
+++ b/tools/clang/unittests/HLSL/ShaderOpTest.cpp
@@ -696,7 +696,7 @@ void ShaderOpTest::CreateShaders() {
       HRESULT resultCode;
       CHECK_HR(m_pDxcSupport->CreateInstance(CLSID_DxcLibrary, &pLibrary));
       CHECK_HR(pLibrary->CreateBlobWithEncodingFromPinned(
-          (LPBYTE)pText, (UINT32)strlen(pText), CP_UTF8, &pTextBlob));
+          pText, (UINT32)strlen(pText), CP_UTF8, &pTextBlob));
       CHECK_HR(m_pDxcSupport->CreateInstance(CLSID_DxcCompiler, &pCompiler));
       CHECK_HR(pCompiler->Compile(pTextBlob, nameW, entryPointW, targetW,
                                   (LPCWSTR *)argumentsWList.data(), argumentsWList.size(),
diff --git a/tools/clang/unittests/HLSL/ValidationTest.cpp b/tools/clang/unittests/HLSL/ValidationTest.cpp
index ef8dafa7c..5b541d2a2 100644
--- a/tools/clang/unittests/HLSL/ValidationTest.cpp
+++ b/tools/clang/unittests/HLSL/ValidationTest.cpp
@@ -279,7 +279,7 @@ public:
     CComPtr<IDxcLibrary> pLibrary;
     CComPtr<IDxcBlobEncoding> pBlobEncoding; // Encoding doesn't actually matter, it's binary.
     VERIFY_SUCCEEDED(m_dllSupport.CreateInstance(CLSID_DxcLibrary, &pLibrary));
-    VERIFY_SUCCEEDED(pLibrary->CreateBlobWithEncodingFromPinned((LPBYTE)pBlob, blobSize, CP_UTF8, &pBlobEncoding));
+    VERIFY_SUCCEEDED(pLibrary->CreateBlobWithEncodingFromPinned(pBlob, blobSize, CP_UTF8, &pBlobEncoding));
     CheckValidationMsgs(pBlobEncoding, pErrorMsgs, bRegex);
   }