diff --git a/source/slang/slang-ast-support-types.h b/source/slang/slang-ast-support-types.h
index a7bbef7af3..1d3de9c546 100644
--- a/source/slang/slang-ast-support-types.h
+++ b/source/slang/slang-ast-support-types.h
@@ -205,8 +205,6 @@ const ImageFormatInfo& getImageFormatInfo(ImageFormat format);
 bool findImageFormatByName(const UnownedStringSlice& name, ImageFormat* outFormat);
 bool findVkImageFormatByName(const UnownedStringSlice& name, ImageFormat* outFormat);
 
-bool isImageFormatSupportedByGLSLAndSPIRV(ImageFormat format);
-
 char const* getGLSLNameForImageFormat(ImageFormat format);
 
 // TODO(tfoley): We should ditch this enumeration
diff --git a/source/slang/slang-emit-glsl.cpp b/source/slang/slang-emit-glsl.cpp
index f6e3212b68..61457d98e5 100644
--- a/source/slang/slang-emit-glsl.cpp
+++ b/source/slang/slang-emit-glsl.cpp
@@ -608,6 +608,19 @@ void GLSLSourceEmitter::_emitGLSLParameterGroup(
     m_writer->emit(";\n");
 }
 
+static bool isImageFormatSupportedByGLSL(ImageFormat format)
+{
+    switch (format)
+    {
+    case ImageFormat::bgra8:
+        // These are formats Slang accept, but are not explicitly supported in GLSL.
+        return false;
+    default:
+        return true;
+    }
+};
+
+
 void GLSLSourceEmitter::_emitGLSLImageFormatModifier(IRInst* var, IRTextureType* resourceType)
 {
     SLANG_UNUSED(resourceType);
@@ -619,7 +632,7 @@ void GLSLSourceEmitter::_emitGLSLImageFormatModifier(IRInst* var, IRTextureType*
     {
         auto format = formatDecoration->getFormat();
         const auto formatInfo = getImageFormatInfo(format);
-        if (!isImageFormatSupportedByGLSLAndSPIRV(format))
+        if (!isImageFormatSupportedByGLSL(format))
         {
             getSink()->diagnose(
                 SourceLoc(),
diff --git a/source/slang/slang-emit-spirv.cpp b/source/slang/slang-emit-spirv.cpp
index c78efe8dcf..7c2e80846d 100644
--- a/source/slang/slang-emit-spirv.cpp
+++ b/source/slang/slang-emit-spirv.cpp
@@ -1905,18 +1905,6 @@ struct SPIRVEmitContext : public SourceEmitterBase, public SPIRVEmitSharedContex
     {
         ImageFormat imageFormat =
             type->hasFormat() ? (ImageFormat)type->getFormat() : ImageFormat::unknown;
-        const auto imageFormatInfo = getImageFormatInfo(imageFormat);
-        if (!isImageFormatSupportedByGLSLAndSPIRV(imageFormat))
-        {
-            m_sink->diagnose(
-                SourceLoc(),
-                Diagnostics::imageFormatUnsupportedByBackend,
-                imageFormatInfo.name,
-                "SPIRV",
-                "unknown");
-            imageFormat = ImageFormat::unknown;
-        }
-
         switch (imageFormat)
         {
         case ImageFormat::unknown:
@@ -2004,7 +1992,14 @@ struct SPIRVEmitContext : public SourceEmitterBase, public SPIRVEmitSharedContex
         case ImageFormat::r64i:
             return SpvImageFormatR64i;
         default:
-            SLANG_UNIMPLEMENTED_X("unknown image format for spirv emit");
+            const auto imageFormatInfo = getImageFormatInfo(imageFormat);
+            m_sink->diagnose(
+                SourceLoc(),
+                Diagnostics::imageFormatUnsupportedByBackend,
+                imageFormatInfo.name,
+                "SPIRV",
+                "unknown");
+            return SpvImageFormatUnknown;
         }
     }
 
diff --git a/source/slang/slang-emit-wgsl.cpp b/source/slang/slang-emit-wgsl.cpp
index 1eb7aabf55..ce60cc2a0e 100644
--- a/source/slang/slang-emit-wgsl.cpp
+++ b/source/slang/slang-emit-wgsl.cpp
@@ -326,7 +326,7 @@ void WGSLSourceEmitter::emit(const AddressSpace addressSpace)
     }
 }
 
-static const char* getWgslImageFormat(IRTextureTypeBase* type)
+const char* WGSLSourceEmitter::getWgslImageFormat(IRTextureTypeBase* type)
 {
     // You can find the supported WGSL texel format from the URL:
     // https://www.w3.org/TR/WGSL/#storage-texel-formats
@@ -411,7 +411,13 @@ static const char* getWgslImageFormat(IRTextureTypeBase* type)
         // Unlike SPIR-V, WGSL doesn't have a texel format for "unknown".
         return "rgba32float";
     default:
-        // We may need to print a warning for types WGSL doesn't support
+        const auto imageFormatInfo = getImageFormatInfo(imageFormat);
+        getSink()->diagnose(
+            SourceLoc(),
+            Diagnostics::imageFormatUnsupportedByBackend,
+            imageFormatInfo.name,
+            "WGSL",
+            "rgba32float");
         return "rgba32float";
     }
 }
diff --git a/source/slang/slang-emit-wgsl.h b/source/slang/slang-emit-wgsl.h
index 4e0c18821d..714a722d7d 100644
--- a/source/slang/slang-emit-wgsl.h
+++ b/source/slang/slang-emit-wgsl.h
@@ -71,6 +71,8 @@ class WGSLSourceEmitter : public CLikeSourceEmitter
         const IRIntegerValue& rowCountWGSL,
         const IRIntegerValue& colCountWGSL);
 
+    const char* getWgslImageFormat(IRTextureTypeBase* type);
+
     bool m_f16ExtensionEnabled = false;
 };
 
diff --git a/source/slang/slang-syntax.cpp b/source/slang/slang-syntax.cpp
index 9170d30ab6..6fdd5088a6 100644
--- a/source/slang/slang-syntax.cpp
+++ b/source/slang/slang-syntax.cpp
@@ -1146,18 +1146,6 @@ bool findVkImageFormatByName(const UnownedStringSlice& name, ImageFormat* outFor
     return findImageFormatByName(name, outFormat);
 }
 
-bool isImageFormatSupportedByGLSLAndSPIRV(ImageFormat format)
-{
-    switch (format)
-    {
-    case ImageFormat::bgra8:
-        // These are formats Slang accept, but are not explicitly supported in GLSL and SPIRV.
-        return false;
-    default:
-        return true;
-    }
-};
-
 char const* getGLSLNameForImageFormat(ImageFormat format)
 {
     return kImageFormatInfos[Index(format)].name.begin();
diff --git a/tests/diagnostics/image-format-unsupported-by-backend.slang b/tests/diagnostics/image-format-unsupported-by-backend.slang
index a9455e76e9..270c2b63e2 100644
--- a/tests/diagnostics/image-format-unsupported-by-backend.slang
+++ b/tests/diagnostics/image-format-unsupported-by-backend.slang
@@ -1,13 +1,19 @@
 //DIAGNOSTIC_TEST:SIMPLE(filecheck=CHECK_SPIRV): -target spirv
-//DIAGNOSTIC_TEST:SIMPLE(filecheck=CHECK_SPIRV): -target glsl
+//DIAGNOSTIC_TEST:SIMPLE(filecheck=CHECK_GLSL): -target glsl
+//DIAGNOSTIC_TEST:SIMPLE(filecheck=CHECK_WGSL): -target wgsl
 
-// CHECK_SPIRV: warning 31105
-// CHECK_GLSL: warning 31105
+// CHECK_SPIRV: warning 31105{{.*}}bgra8
+// CHECK_GLSL: warning 31105{{.*}}bgra8
 [format("bgra8")]
 RWTexture2D<float4> outputTexture;
 
+// CHECK_WGSL: warning 31105{{.*}}rg8
+[format("rg8")]
+RWTexture2D<float4> outputTexture2;
+
 [numthreads(8, 8, 1)]
 void main(uint3 threadID : SV_DispatchThreadID)
 {
     outputTexture[threadID.xy] = float4(1.0, 1.0, 1.0, 1.0);
+    outputTexture2[threadID.xy] = float4(1.0, 1.0, 1.0, 1.0);
 }