diff --git a/src/imageio.cpp b/src/imageio.cpp
index 8f2323b..577328d 100644
--- a/src/imageio.cpp
+++ b/src/imageio.cpp
@@ -34,7 +34,7 @@ SDL_Surface *loadPNG(const std::string &path) {
 #ifdef HAVE_LIBOPK
 	std::string::size_type pos;
 	struct ParserData *pdata = NULL;
-	char *buffer = NULL, *param;
+	void *buffer = NULL, *param;
 #endif
 
 	// Create and initialize the top-level libpng struct.
diff --git a/src/linkapp.cpp b/src/linkapp.cpp
index 474dce1..aea661d 100644
--- a/src/linkapp.cpp
+++ b/src/linkapp.cpp
@@ -387,7 +387,8 @@ void LinkApp::showManual() {
 			return;
 		}
 
-		buf = ptr = opk_extract_file(pdata, manual.c_str());
+		buf = ptr = reinterpret_cast<char *>(
+				opk_extract_file(pdata, manual.c_str()));
 		opk_close(pdata);
 
 		if (!buf) {