diff --git a/src/include/OpenImageIO/deepdata.h b/src/include/OpenImageIO/deepdata.h
index 5a1d1e0404..ef0fd5595e 100644
--- a/src/include/OpenImageIO/deepdata.h
+++ b/src/include/OpenImageIO/deepdata.h
@@ -188,7 +188,8 @@ class OIIO_API DeepData {
     /// Merge the samples of `src`'s pixel into this `DeepData`'s pixel.
     /// Return `true` if ok, `false` if the operation could not be
     /// performed.
-    void merge_deep_pixels(int64_t pixel, const DeepData& src, int srcpixel);
+    void merge_deep_pixels(int64_t pixel, const DeepData& src,
+                           int64_t srcpixel);
 
     /// Return the z depth at which the pixel reaches full opacity.
     float opaque_z(int64_t pixel) const;
diff --git a/src/libOpenImageIO/deepdata.cpp b/src/libOpenImageIO/deepdata.cpp
index ff015fb346..dd2725b3aa 100644
--- a/src/libOpenImageIO/deepdata.cpp
+++ b/src/libOpenImageIO/deepdata.cpp
@@ -1176,7 +1176,8 @@ DeepData::merge_overlaps(int64_t pixel)
 
 
 void
-DeepData::merge_deep_pixels(int64_t pixel, const DeepData& src, int srcpixel)
+DeepData::merge_deep_pixels(int64_t pixel, const DeepData& src,
+                            int64_t srcpixel)
 {
     int srcsamples = src.samples(srcpixel);
     if (srcsamples == 0)