diff --git a/src/webp/decode.h b/src/webp/decode.h
index dd7bf999..8ffddb81 100644
--- a/src/webp/decode.h
+++ b/src/webp/decode.h
@@ -23,8 +23,10 @@ extern "C" {
 typedef struct WebPRGBABuffer WebPRGBABuffer;
 typedef struct WebPYUVABuffer WebPYUVABuffer;
 typedef struct WebPDecBuffer WebPDecBuffer;
+#if !(defined(__cplusplus) || defined(c_plusplus))
 typedef enum VP8StatusCode VP8StatusCode;
 typedef enum WEBP_CSP_MODE WEBP_CSP_MODE;
+#endif
 typedef struct WebPIDecoder WebPIDecoder;
 typedef struct WebPBitstreamFeatures WebPBitstreamFeatures;
 typedef struct WebPDecoderOptions WebPDecoderOptions;
diff --git a/src/webp/encode.h b/src/webp/encode.h
index b9a61472..40e98236 100644
--- a/src/webp/encode.h
+++ b/src/webp/encode.h
@@ -20,14 +20,16 @@ extern "C" {
 
 #define WEBP_ENCODER_ABI_VERSION 0x0200    // MAJOR(8b) + MINOR(8b)
 
+#if !(defined(__cplusplus) || defined(c_plusplus))
 typedef enum WebPImageHint WebPImageHint;
 typedef enum WebPEncCSP WebPEncCSP;
-typedef struct WebPConfig WebPConfig;
 typedef enum WebPPreset WebPPreset;
+typedef enum WebPEncodingError WebPEncodingError;
+#endif
+typedef struct WebPConfig WebPConfig;
 typedef struct WebPPicture WebPPicture;   // main structure for I/O
 typedef struct WebPAuxStats WebPAuxStats;
 typedef struct WebPMemoryWriter WebPMemoryWriter;
-typedef enum WebPEncodingError WebPEncodingError;
 
 // Return the encoder's version number, packed in hexadecimal using 8bits for
 // each of major/minor/revision. E.g: v2.5.7 is 0x020507.
diff --git a/src/webp/mux.h b/src/webp/mux.h
index 73d83a78..81e19397 100644
--- a/src/webp/mux.h
+++ b/src/webp/mux.h
@@ -55,14 +55,18 @@ extern "C" {
 
 typedef struct WebPMux WebPMux;   // main opaque object.
 typedef struct WebPData WebPData;
+#if !(defined(__cplusplus) || defined(c_plusplus))
 typedef enum WebPMuxError WebPMuxError;
 typedef enum WebPFeatureFlags WebPFeatureFlags;
 typedef enum WebPChunkId WebPChunkId;
+#endif
 typedef struct WebPMuxFrameInfo WebPMuxFrameInfo;
 
 typedef struct WebPDemuxer WebPDemuxer;
+#if !(defined(__cplusplus) || defined(c_plusplus))
 typedef enum WebPDemuxState WebPDemuxState;
 typedef enum WebPFormatFeature WebPFormatFeature;
+#endif
 typedef struct WebPIterator WebPIterator;
 typedef struct WebPChunkIterator WebPChunkIterator;