diff --git a/auto/src/glew_init_gl.c b/auto/src/glew_init_gl.c
index b28013f..d3b0914 100644
--- a/auto/src/glew_init_gl.c
+++ b/auto/src/glew_init_gl.c
@@ -79,7 +79,6 @@ static GLenum GLEWAPIENTRY glewContextInit ()
   const GLubyte* s;
   GLuint dot;
   GLint major, minor;
-  size_t n;
 
   #ifdef _WIN32
   getString = glGetString;
@@ -130,8 +129,11 @@ static GLenum GLEWAPIENTRY glewContextInit ()
     GLEW_VERSION_1_1   = GLEW_VERSION_1_2   == GL_TRUE || ( major == 1 && minor >= 1 ) ? GL_TRUE : GL_FALSE;
   }
 
-  for (n = 0; n < sizeof(_glewExtensionString) / sizeof(_glewExtensionString[0]); ++n)
-    _glewExtensionString[n] = GL_FALSE;
+  {
+    size_t i;
+    for (i = 0; i < sizeof(_glewExtensionString) / sizeof(_glewExtensionString[0]); ++i)
+      _glewExtensionString[i] = GL_FALSE;
+  }
 
   if (GLEW_VERSION_3_0)
   {
diff --git a/config/Makefile.linux b/config/Makefile.linux
index 5263ada..694a98d 100644
--- a/config/Makefile.linux
+++ b/config/Makefile.linux
@@ -23,7 +23,9 @@ LDFLAGS.GL = -lGL -lX11
 LDFLAGS.STATIC = -Wl,-Bstatic
 LDFLAGS.DYNAMIC = -Wl,-Bdynamic
 NAME = GLEW
-WARN = -Wall -W
+WARN += -Wall -W
+WARN += -Wshadow
+WARN += -pedantic
 POPT = -O2
 CFLAGS.EXTRA += -fPIC
 CFLAGS.EXTRA += -Wcast-qual