diff --git a/src/cairo-wideint-private.h b/src/cairo-wideint-private.h
index 1841a44..5ebfae8 100644
--- a/src/cairo-wideint-private.h
+++ b/src/cairo-wideint-private.h
@@ -76,7 +76,7 @@ #endif
 
 #define I cairo_private
 
-#if !HAVE_UINT64_T
+#ifndef HAVE_UINT64_T
 
 typedef struct _cairo_uint64 {
     uint32_t	lo, hi;
@@ -195,7 +195,7 @@ _cairo_int64_divrem (cairo_int64_t num, 
  * on ia64
  */
 
-#if !HAVE_UINT128_T
+#ifndef HAVE_UINT128_T
 
 typedef struct cairo_uint128 {
     cairo_uint64_t	lo, hi;
diff --git a/src/cairo-xlib-screen.c b/src/cairo-xlib-screen.c
index cbdb540..c85f222 100644
--- a/src/cairo-xlib-screen.c
+++ b/src/cairo-xlib-screen.c
@@ -377,7 +377,7 @@ _cairo_xlib_screen_reset_static_data (vo
 {
     _cairo_xlib_screen_info_reset ();
 
-#if HAVE_XRMFINALIZE
+#ifdef HAVE_XRMFINALIZE
     XrmFinalize ();
 #endif
 
diff --git a/src/cairoint.h b/src/cairoint.h
index 06fc8d4..5529eb9 100755
--- a/src/cairoint.h
+++ b/src/cairoint.h
@@ -46,7 +46,7 @@
 #ifndef _CAIROINT_H_
 #define _CAIROINT_H_
 
-#if HAVE_CONFIG_H
+#ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
 
@@ -139,7 +139,7 @@ #else
 #define INLINE
 #endif
 
-#if HAVE_PTHREAD_H
+#ifdef HAVE_PTHREAD_H
 # include <pthread.h>
 # define CAIRO_MUTEX_DECLARE(name) static pthread_mutex_t name = PTHREAD_MUTEX_INITIALIZER
 #define CAIRO_MUTEX_DECLARE_GLOBAL(name) pthread_mutex_t name = PTHREAD_MUTEX_INITIALIZER
@@ -662,13 +662,13 @@ extern const cairo_private struct _cairo
 
 #endif
 
-#if CAIRO_HAS_WIN32_FONT
+#ifdef CAIRO_HAS_WIN32_FONT
 
 extern const cairo_private struct _cairo_scaled_font_backend cairo_win32_scaled_font_backend;
 
 #endif
 
-#if CAIRO_HAS_ATSUI_FONT
+#ifdef CAIRO_HAS_ATSUI_FONT
 
 extern const cairo_private struct _cairo_scaled_font_backend cairo_atsui_scaled_font_backend;
 
@@ -1106,17 +1106,21 @@ #define CAIRO_WIN32_FONT_FAMILY_DEFAULT 
 #define CAIRO_ATSUI_FONT_FAMILY_DEFAULT  "Monaco"
 #define CAIRO_FT_FONT_FAMILY_DEFAULT     ""
 
-#if   CAIRO_HAS_WIN32_FONT
+#ifdef   CAIRO_HAS_WIN32_FONT
 
 #define CAIRO_FONT_FAMILY_DEFAULT CAIRO_WIN32_FONT_FAMILY_DEFAULT
 #define CAIRO_SCALED_FONT_BACKEND_DEFAULT &cairo_win32_scaled_font_backend
 
-#elif CAIRO_HAS_ATSUI_FONT
+#endif
+
+#ifdef CAIRO_HAS_ATSUI_FONT
 
 #define CAIRO_FONT_FAMILY_DEFAULT CAIRO_ATSUI_FONT_FAMILY_DEFAULT
 #define CAIRO_SCALED_FONT_BACKEND_DEFAULT &cairo_atsui_scaled_font_backend
 
-#elif CAIRO_HAS_FT_FONT
+#endif
+
+#ifdef CAIRO_HAS_FT_FONT
 
 #define CAIRO_FONT_FAMILY_DEFAULT CAIRO_FT_FONT_FAMILY_DEFAULT
 #define CAIRO_SCALED_FONT_BACKEND_DEFAULT &cairo_ft_scaled_font_backend