diff --git a/src/core.h b/src/core.h
index 29c47061..55a18d37 100644
--- a/src/core.h
+++ b/src/core.h
@@ -47,6 +47,7 @@
 
 /* Ensure isnan() is present even on systems that don't define it, or
  * when -ffast-math is being used. */
+#include <cmath>
 #if defined __FAST_MATH__
 #   undef isnan
 #endif
diff --git a/src/image/codec/android-image.cpp b/src/image/codec/android-image.cpp
index 93fac056..b752ec45 100644
--- a/src/image/codec/android-image.cpp
+++ b/src/image/codec/android-image.cpp
@@ -95,7 +95,7 @@ bool AndroidImageData::Open(char const *path)
         u = (u & 0xff00ff00) | ((u & 0xff0000) >> 16) | ((u & 0xff) << 16);
         pixels[n] = u;
     }
-    format = FORMAT_RGBA;
+    format = Image::FORMAT_RGBA;
 
     return true;
 }
diff --git a/src/image/codec/ps3-image.cpp b/src/image/codec/ps3-image.cpp
index 03f15954..5efdae03 100644
--- a/src/image/codec/ps3-image.cpp
+++ b/src/image/codec/ps3-image.cpp
@@ -78,9 +78,9 @@ bool Ps3ImageData::Open(char const *path)
     in_param.spuThreadEnable = CELL_PNGDEC_SPU_THREAD_ENABLE;
     in_param.ppuThreadPriority = 1000;
     in_param.spuThreadPriority = 200;
-    in_param.cbCtrlMallocFunc = ImageData::Malloc;
+    in_param.cbCtrlMallocFunc = Ps3ImageData::Malloc;
     in_param.cbCtrlMallocArg = NULL;
-    in_param.cbCtrlFreeFunc = ImageData::Free;
+    in_param.cbCtrlFreeFunc = Ps3ImageData::Free;
     in_param.cbCtrlFreeArg = NULL;
     CellPngDecThreadOutParam out_param;
     err = cellPngDecCreate(&hmain, &in_param, &out_param);
@@ -146,7 +146,7 @@ bool Ps3ImageData::Open(char const *path)
 
     /* Decode image */
     size = ivec2(info.imageWidth, info.imageHeight);
-    format = FORMAT_RGBA;
+    format = Image::FORMAT_RGBA;
     pixels = (uint8_t *)malloc(info.imageWidth * 4 * info.imageHeight);
     CellPngDecDataCtrlParam data_ctrl_param;
     data_ctrl_param.outputBytesPerLine = info.imageWidth * 4;
diff --git a/src/image/image-private.h b/src/image/image-private.h
index b03b1d72..5532f304 100644
--- a/src/image/image-private.h
+++ b/src/image/image-private.h
@@ -75,6 +75,8 @@ class ImageData
     friend class Image;
 
 public:
+    virtual ~ImageData() {}
+
     virtual bool Open(char const *) = 0;
     virtual bool Close() = 0;
 
@@ -83,8 +85,6 @@ public:
 protected:
     ivec2 size;
     Image::format_t format;
-
-private:
 };
 
 #define REGISTER_IMAGE_LOADER(name) \