diff --git a/src/api/android/mod.rs b/src/api/android/mod.rs
index 23440d35fba..3dcea902ec7 100644
--- a/src/api/android/mod.rs
+++ b/src/api/android/mod.rs
@@ -263,7 +263,7 @@ impl GlContext for Window {
     }
 
     #[inline]
-    fn get_proc_address(&self, addr: &str) -> *const libc::c_void {
+    fn get_proc_address(&self, addr: &str) -> *const () {
         self.context.get_proc_address(addr)
     }
 
@@ -323,7 +323,7 @@ impl GlContext for HeadlessContext {
     }
 
     #[inline]
-    fn get_proc_address(&self, addr: &str) -> *const libc::c_void {
+    fn get_proc_address(&self, addr: &str) -> *const () {
         self.0.get_proc_address(addr)
     }
 
diff --git a/src/api/caca/mod.rs b/src/api/caca/mod.rs
index 43742f31b14..687c66fed27 100644
--- a/src/api/caca/mod.rs
+++ b/src/api/caca/mod.rs
@@ -252,7 +252,7 @@ impl GlContext for Window {
     }
 
     #[inline]
-    fn get_proc_address(&self, addr: &str) -> *const libc::c_void {
+    fn get_proc_address(&self, addr: &str) -> *const () {
         self.opengl.get_proc_address(addr)
     }
 
diff --git a/src/api/cocoa/headless.rs b/src/api/cocoa/headless.rs
index 49b8bc3c8ad..1318185d1b7 100644
--- a/src/api/cocoa/headless.rs
+++ b/src/api/cocoa/headless.rs
@@ -91,7 +91,7 @@ impl GlContext for HeadlessContext {
     }
 
     #[inline]
-    fn get_proc_address(&self, _addr: &str) -> *const libc::c_void {
+    fn get_proc_address(&self, _addr: &str) -> *const () {
         let symbol_name: CFString = _addr.parse().unwrap();
         let framework_name: CFString = "com.apple.opengl".parse().unwrap();
         let framework = unsafe {
@@ -100,7 +100,7 @@ impl GlContext for HeadlessContext {
         let symbol = unsafe {
             CFBundleGetFunctionPointerForName(framework, symbol_name.as_concrete_TypeRef())
         };
-        symbol as *const libc::c_void
+        symbol as *const ()
     }
 
     #[inline]
diff --git a/src/api/cocoa/mod.rs b/src/api/cocoa/mod.rs
index 2b4b5e5f08c..06ff751f40f 100644
--- a/src/api/cocoa/mod.rs
+++ b/src/api/cocoa/mod.rs
@@ -777,7 +777,7 @@ impl GlContext for Window {
         }
     }
 
-    fn get_proc_address(&self, addr: &str) -> *const libc::c_void {
+    fn get_proc_address(&self, addr: &str) -> *const () {
         let symbol_name: CFString = FromStr::from_str(addr).unwrap();
         let framework_name: CFString = FromStr::from_str("com.apple.opengl").unwrap();
         let framework = unsafe {
diff --git a/src/api/egl/mod.rs b/src/api/egl/mod.rs
index 0c0ec1f70dd..53f8fc9a582 100644
--- a/src/api/egl/mod.rs
+++ b/src/api/egl/mod.rs
@@ -284,7 +284,7 @@ impl GlContext for Context {
         unsafe { self.egl.GetCurrentContext() == self.context }
     }
 
-    fn get_proc_address(&self, addr: &str) -> *const libc::c_void {
+    fn get_proc_address(&self, addr: &str) -> *const () {
         let addr = CString::new(addr.as_bytes()).unwrap();
         let addr = addr.as_ptr();
         unsafe {
diff --git a/src/api/emscripten/mod.rs b/src/api/emscripten/mod.rs
index 91304f0089c..61d8c8ccc4f 100644
--- a/src/api/emscripten/mod.rs
+++ b/src/api/emscripten/mod.rs
@@ -221,7 +221,7 @@ impl GlContext for Window {
         true        // FIXME: 
     }
 
-    fn get_proc_address(&self, addr: &str) -> *const libc::c_void {
+    fn get_proc_address(&self, addr: &str) -> *const () {
         let addr = CString::new(addr.as_bytes()).unwrap();
         let addr = addr.as_ptr();
 
diff --git a/src/api/glx/mod.rs b/src/api/glx/mod.rs
index a7f866256d6..61a7d2fe13f 100644
--- a/src/api/glx/mod.rs
+++ b/src/api/glx/mod.rs
@@ -82,7 +82,7 @@ impl GlContext for Context {
         unsafe { self.glx.GetCurrentContext() == self.context }
     }
 
-    fn get_proc_address(&self, addr: &str) -> *const libc::c_void {
+    fn get_proc_address(&self, addr: &str) -> *const () {
         let addr = CString::new(addr.as_bytes()).unwrap();
         let addr = addr.as_ptr();
         unsafe {
diff --git a/src/api/ios/mod.rs b/src/api/ios/mod.rs
index 52eebbf3781..852d97c3f7f 100644
--- a/src/api/ios/mod.rs
+++ b/src/api/ios/mod.rs
@@ -384,12 +384,12 @@ impl GlContext for Window {
         false
     }
 
-    fn get_proc_address(&self, addr: &str) -> *const libc::c_void {
+    fn get_proc_address(&self, addr: &str) -> *const () {
         let addr_c = CString::new(addr).unwrap();
         let path = CString::new("/System/Library/Frameworks/OpenGLES.framework/OpenGLES").unwrap();
         unsafe {
             let lib = dlopen(path.as_ptr(), RTLD_LAZY | RTLD_GLOBAL);
-            dlsym(lib, addr_c.as_ptr())
+            dlsym(lib, addr_c.as_ptr()) as *const _
         }
     }
 
diff --git a/src/api/osmesa/mod.rs b/src/api/osmesa/mod.rs
index 065ffc68649..02c43a11b6e 100644
--- a/src/api/osmesa/mod.rs
+++ b/src/api/osmesa/mod.rs
@@ -106,7 +106,7 @@ impl GlContext for OsMesaContext {
         unsafe { osmesa_sys::OSMesaGetCurrentContext() == self.context }
     }
 
-    fn get_proc_address(&self, addr: &str) -> *const libc::c_void {
+    fn get_proc_address(&self, addr: &str) -> *const () {
         unsafe {
             let c_str = CString::new(addr.as_bytes().to_vec()).unwrap();
             mem::transmute(osmesa_sys::OSMesaGetProcAddress(mem::transmute(c_str.as_ptr())))
diff --git a/src/api/wayland/mod.rs b/src/api/wayland/mod.rs
index 81acbf0c8eb..2877713ea4e 100644
--- a/src/api/wayland/mod.rs
+++ b/src/api/wayland/mod.rs
@@ -456,7 +456,7 @@ impl GlContext for Window {
     }
 
     #[inline]
-    fn get_proc_address(&self, addr: &str) -> *const libc::c_void {
+    fn get_proc_address(&self, addr: &str) -> *const () {
         self.context.get_proc_address(addr)
     }
 
diff --git a/src/api/wgl/mod.rs b/src/api/wgl/mod.rs
index f064931564e..0f6a94420ae 100644
--- a/src/api/wgl/mod.rs
+++ b/src/api/wgl/mod.rs
@@ -171,7 +171,7 @@ impl GlContext for Context {
         unsafe { gl::wgl::GetCurrentContext() == self.context.0 as *const libc::c_void }
     }
 
-    fn get_proc_address(&self, addr: &str) -> *const libc::c_void {
+    fn get_proc_address(&self, addr: &str) -> *const () {
         let addr = CString::new(addr.as_bytes()).unwrap();
         let addr = addr.as_ptr();
 
diff --git a/src/api/win32/mod.rs b/src/api/win32/mod.rs
index 4fb3635cd2a..d85ef0998f1 100644
--- a/src/api/win32/mod.rs
+++ b/src/api/win32/mod.rs
@@ -365,7 +365,7 @@ impl GlContext for Window {
     }
 
     #[inline]
-    fn get_proc_address(&self, addr: &str) -> *const libc::c_void {
+    fn get_proc_address(&self, addr: &str) -> *const () {
         match self.context {
             Context::Wgl(ref c) => c.get_proc_address(addr),
             Context::Egl(ref c) => c.get_proc_address(addr),
diff --git a/src/api/x11/window.rs b/src/api/x11/window.rs
index 72b9b331ce9..b964fed6f8e 100644
--- a/src/api/x11/window.rs
+++ b/src/api/x11/window.rs
@@ -807,7 +807,7 @@ impl GlContext for Window {
     }
 
     #[inline]
-    fn get_proc_address(&self, addr: &str) -> *const libc::c_void {
+    fn get_proc_address(&self, addr: &str) -> *const () {
         match self.x.context {
             Context::Glx(ref ctxt) => ctxt.get_proc_address(addr),
             Context::Egl(ref ctxt) => ctxt.get_proc_address(addr),
diff --git a/src/headless.rs b/src/headless.rs
index 23177944c53..67ea8daa70a 100644
--- a/src/headless.rs
+++ b/src/headless.rs
@@ -8,9 +8,6 @@ use PixelFormat;
 use PixelFormatRequirements;
 use Robustness;
 
-use gl_common;
-use libc;
-
 use platform;
 
 /// Object that allows you to build headless contexts.
@@ -103,8 +100,8 @@ impl HeadlessContext {
     ///
     /// Contrary to `wglGetProcAddress`, all available OpenGL functions return an address.
     #[inline]
-    pub fn get_proc_address(&self, addr: &str) -> *const libc::c_void {
-        self.context.get_proc_address(addr) as *const libc::c_void
+    pub fn get_proc_address(&self, addr: &str) -> *const () {
+        self.context.get_proc_address(addr)
     }
 
     /// Returns the API that is currently provided by this window.
@@ -120,13 +117,6 @@ impl HeadlessContext {
     }
 }
 
-impl gl_common::GlFunctionsSource for HeadlessContext {
-    #[inline]
-    fn get_proc_addr(&self, addr: &str) -> *const libc::c_void {
-        self.get_proc_address(addr)
-    }
-}
-
 impl GlContext for HeadlessContext {
     #[inline]
     unsafe fn make_current(&self) -> Result<(), ContextError> {
@@ -139,7 +129,7 @@ impl GlContext for HeadlessContext {
     }
 
     #[inline]
-    fn get_proc_address(&self, addr: &str) -> *const libc::c_void {
+    fn get_proc_address(&self, addr: &str) -> *const () {
         self.context.get_proc_address(addr)
     }
 
diff --git a/src/lib.rs b/src/lib.rs
index b62c4a05ce0..a1fa54f8cb8 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -112,7 +112,7 @@ pub trait GlContext {
     fn is_current(&self) -> bool;
 
     /// Returns the address of an OpenGL function.
-    fn get_proc_address(&self, addr: &str) -> *const libc::c_void;
+    fn get_proc_address(&self, addr: &str) -> *const ();
 
     /// Swaps the buffers in case of double or triple buffering.
     ///
diff --git a/src/platform/emscripten/mod.rs b/src/platform/emscripten/mod.rs
index 0d059d7b29f..270cdaf2fe0 100644
--- a/src/platform/emscripten/mod.rs
+++ b/src/platform/emscripten/mod.rs
@@ -28,7 +28,7 @@ impl GlContext for HeadlessContext {
     }
 
     #[inline]
-    fn get_proc_address(&self, addr: &str) -> *const libc::c_void {
+    fn get_proc_address(&self, addr: &str) -> *const () {
         self.0.get_proc_address(addr)
     }
 
diff --git a/src/platform/ios/mod.rs b/src/platform/ios/mod.rs
index 95fa7e1a7f5..aeaebc32191 100644
--- a/src/platform/ios/mod.rs
+++ b/src/platform/ios/mod.rs
@@ -1,5 +1,4 @@
 #![cfg(target_os = "ios")]
-use libc::c_void;
 
 use GlAttributes;
 use CreationError;
@@ -33,7 +32,7 @@ impl HeadlessContext {
     }
 
     /// See the docs in the crate root file.
-    pub fn get_proc_address(&self, _addr: &str) -> *const c_void {
+    pub fn get_proc_address(&self, _addr: &str) -> *const () {
         unimplemented!()
     }
 
diff --git a/src/platform/linux/api_dispatch.rs b/src/platform/linux/api_dispatch.rs
index aa1ba58f6ef..a3c3bf9db9d 100644
--- a/src/platform/linux/api_dispatch.rs
+++ b/src/platform/linux/api_dispatch.rs
@@ -359,7 +359,7 @@ impl GlContext for Window {
     }
 
     #[inline]
-    fn get_proc_address(&self, addr: &str) -> *const libc::c_void {
+    fn get_proc_address(&self, addr: &str) -> *const () {
         match self {
             &Window::X(ref w) => w.get_proc_address(addr),
             &Window::Wayland(ref w) => w.get_proc_address(addr)
diff --git a/src/platform/linux/mod.rs b/src/platform/linux/mod.rs
index c9849269a58..d010a897d78 100644
--- a/src/platform/linux/mod.rs
+++ b/src/platform/linux/mod.rs
@@ -7,7 +7,6 @@ use GlAttributes;
 use GlContext;
 use PixelFormat;
 use PixelFormatRequirements;
-use libc;
 
 use api::osmesa::{self, OsMesaContext};
 
@@ -45,7 +44,7 @@ impl GlContext for HeadlessContext {
     }
 
     #[inline]
-    fn get_proc_address(&self, addr: &str) -> *const libc::c_void {
+    fn get_proc_address(&self, addr: &str) -> *const () {
         self.0.get_proc_address(addr)
     }
 
diff --git a/src/platform/windows/mod.rs b/src/platform/windows/mod.rs
index a280316a4ef..246ca51b300 100644
--- a/src/platform/windows/mod.rs
+++ b/src/platform/windows/mod.rs
@@ -4,8 +4,6 @@ pub use api::win32;
 pub use api::win32::{MonitorId, get_available_monitors, get_primary_monitor};
 pub use api::win32::{WindowProxy, PollEventsIterator, WaitEventsIterator};
 
-use libc;
-
 use Api;
 use ContextError;
 use CreationError;
@@ -134,7 +132,7 @@ impl GlContext for HeadlessContext {
     }
 
     #[inline]
-    fn get_proc_address(&self, addr: &str) -> *const libc::c_void {
+    fn get_proc_address(&self, addr: &str) -> *const () {
         match self {
             &HeadlessContext::HiddenWindow(ref ctxt) => ctxt.get_proc_address(addr),
             &HeadlessContext::EglPbuffer(ref ctxt) => ctxt.get_proc_address(addr),
diff --git a/src/window.rs b/src/window.rs
index 7a87806d87d..86322bd2926 100644
--- a/src/window.rs
+++ b/src/window.rs
@@ -18,9 +18,7 @@ use Window;
 use WindowAttributes;
 use native_monitor::NativeMonitorId;
 
-use gl_common;
 use libc;
-
 use platform;
 
 /// Object that allows you to build windows.
@@ -397,8 +395,8 @@ impl Window {
     ///
     /// Contrary to `wglGetProcAddress`, all available OpenGL functions return an address.
     #[inline]
-    pub fn get_proc_address(&self, addr: &str) -> *const libc::c_void {
-        self.window.get_proc_address(addr) as *const libc::c_void
+    pub fn get_proc_address(&self, addr: &str) -> *const () {
+        self.window.get_proc_address(addr)
     }
 
     /// Swaps the buffers in case of double or triple buffering.
@@ -492,13 +490,6 @@ impl Window {
     }
 }
 
-impl gl_common::GlFunctionsSource for Window {
-    #[inline]
-    fn get_proc_addr(&self, addr: &str) -> *const libc::c_void {
-        self.get_proc_address(addr)
-    }
-}
-
 impl GlContext for Window {
     #[inline]
     unsafe fn make_current(&self) -> Result<(), ContextError> {
@@ -511,7 +502,7 @@ impl GlContext for Window {
     }
 
     #[inline]
-    fn get_proc_address(&self, addr: &str) -> *const libc::c_void {
+    fn get_proc_address(&self, addr: &str) -> *const () {
         self.get_proc_address(addr)
     }