diff --git a/dlls/opengl32/wgl.c b/dlls/opengl32/wgl.c
index 8ef0ba1cf73..f21f05dd5d8 100644
--- a/dlls/opengl32/wgl.c
+++ b/dlls/opengl32/wgl.c
@@ -360,7 +360,7 @@ void* WINAPI wglGetProcAddress(LPCSTR  lpszProc) {
     if (wgl_ext_ret == NULL) {
       /* Some sanity checks :-) */
       ENTER_GL();
-      local_func = p_glXGetProcAddressARB(lpszProc);
+      local_func = p_glXGetProcAddressARB( (const GLubyte *) lpszProc);
       LEAVE_GL();
       if (local_func != NULL) {
 	WARN("Extension %s defined in the OpenGL library but NOT in opengl_ext.c...\n", lpszProc);
@@ -391,7 +391,7 @@ void* WINAPI wglGetProcAddress(LPCSTR  lpszProc) {
     }
   } else {
     ENTER_GL();
-    local_func = p_glXGetProcAddressARB(ext_ret->glx_name);
+    local_func = p_glXGetProcAddressARB( (const GLubyte*) ext_ret->glx_name);
     LEAVE_GL();
     
     /* After that, look at the extensions defined in the Linux OpenGL library */
@@ -762,7 +762,7 @@ const GLubyte * internal_glGetString(GLenum name) {
   }
 
   if (NULL == internal_gl_extensions) {
-    GL_Extensions = glGetString(GL_EXTENSIONS);
+    GL_Extensions = (const char *) glGetString(GL_EXTENSIONS);
 
     TRACE("GL_EXTENSIONS reported:\n");  
     if (NULL == GL_Extensions) {
@@ -796,7 +796,7 @@ const GLubyte * internal_glGetString(GLenum name) {
       }
     }
   }
-  return internal_gl_extensions;
+  return (const GLubyte *) internal_gl_extensions;
 }
 
 
diff --git a/dlls/opengl32/wgl_ext.c b/dlls/opengl32/wgl_ext.c
index bf7b78c838e..335554ab014 100644
--- a/dlls/opengl32/wgl_ext.c
+++ b/dlls/opengl32/wgl_ext.c
@@ -138,9 +138,9 @@ BOOL query_function_render_texture(glXGetProcAddressARB_t proc, const char *gl_v
   BOOL bTest = (0 <= strcmp("1.3", glx_version) || NULL != strstr(glx_extensions, "GLX_SGIX_pbuffer"));
   if (bTest) {
     if (NULL != strstr(glx_extensions, "GLX_ARB_render_texture")) {
-      p_glXBindTexImageARB = proc("glXBindTexImageARB");
-      p_glXReleaseTexImageARB = proc("glXReleaseTexImageARB");
-      p_glXDrawableAttribARB = proc("glXDrawableAttribARB");
+      p_glXBindTexImageARB = proc( (const GLubyte *) "glXBindTexImageARB");
+      p_glXReleaseTexImageARB = proc( (const GLubyte *) "glXReleaseTexImageARB");
+      p_glXDrawableAttribARB = proc( (const GLubyte *) "glXDrawableAttribARB");
       bTest = (NULL != p_glXBindTexImageARB && NULL != p_glXReleaseTexImageARB && NULL != p_glXDrawableAttribARB);
     } else {
       use_render_texture_emulation = 0;
@@ -156,7 +156,7 @@ BOOL query_function_swap_control(glXGetProcAddressARB_t proc, const char *gl_ver
 {
   BOOL bTest = (0 <= strcmp("1.3", glx_version) || NULL != strstr(glx_extensions, "GLX_SGI_swap_control"));
   if (bTest) {
-    p_glXSwapIntervalSGI = proc("glXSwapIntervalSGI");
+    p_glXSwapIntervalSGI = proc( (const GLubyte *) "glXSwapIntervalSGI");
     bTest = (NULL != p_glXSwapIntervalSGI);
   }
   return bTest;
@@ -901,10 +901,10 @@ GLboolean WINAPI wglQueryPbufferARB(HPBUFFERARB hPbuffer, int iAttribute, int *p
   }
   switch (iAttribute) {
   case WGL_PBUFFER_WIDTH_ARB:
-    glXQueryDrawable(object->display, object->drawable, GLX_WIDTH, piValue);
+    glXQueryDrawable(object->display, object->drawable, GLX_WIDTH, (unsigned int*) piValue);
     break;
   case WGL_PBUFFER_HEIGHT_ARB:
-    glXQueryDrawable(object->display, object->drawable, GLX_HEIGHT, piValue);
+    glXQueryDrawable(object->display, object->drawable, GLX_HEIGHT, (unsigned int*) piValue);
     break;
 
   case WGL_PBUFFER_LOST_ARB:
@@ -967,7 +967,7 @@ GLboolean WINAPI wglReleaseTexImageARB(HPBUFFERARB hPbuffer, int iBuffer)
     return GL_FALSE;
   }
   if (1 == use_render_texture_emulation) {
-    GLuint prev_binded_tex;
+    GLint prev_binded_tex;
     glGetIntegerv(object->texture_target, &prev_binded_tex);
     glBindTexture(object->texture_target, object->texture);
     if (GL_TEXTURE_1D == object->texture_target) {