diff --git a/basis/cairo/ffi/ffi.factor b/basis/cairo/ffi/ffi.factor
index bca02c1f17..dc68af64dc 100644
--- a/basis/cairo/ffi/ffi.factor
+++ b/basis/cairo/ffi/ffi.factor
@@ -786,7 +786,7 @@ FUNCTION: int
 cairo_format_stride_for_width ( cairo_format_t format, int width ) ;
 
 FUNCTION: cairo_surface_t*
-cairo_image_surface_create_for_data ( c-string data, cairo_format_t format, int width, int height, int stride ) ;
+cairo_image_surface_create_for_data ( char* data, cairo_format_t format, int width, int height, int stride ) ;
 
 FUNCTION: c-string
 cairo_image_surface_get_data ( cairo_surface_t* surface ) ;
diff --git a/basis/core-foundation/strings/strings.factor b/basis/core-foundation/strings/strings.factor
index 9a91335ae2..4c7e9ba261 100644
--- a/basis/core-foundation/strings/strings.factor
+++ b/basis/core-foundation/strings/strings.factor
@@ -37,7 +37,7 @@ FUNCTION: void CFStringGetCharacters ( void* theString, CFIndex start, CFIndex l
 
 FUNCTION: Boolean CFStringGetCString (
     CFStringRef theString,
-    c-string buffer,
+    UInt8* buffer,
     CFIndex bufferSize,
     CFStringEncoding encoding
 ) ;
@@ -55,7 +55,7 @@ FUNCTION: CFIndex CFStringGetBytes (
 
 FUNCTION: CFStringRef CFStringCreateWithCString (
     CFAllocatorRef alloc,
-    c-string cStr,
+    UInt8* cStr,
     CFStringEncoding encoding
 ) ;