diff --git a/glib/gbacktrace.c b/glib/gbacktrace.c
index 0f81502e5..ce9f4ff91 100644
--- a/glib/gbacktrace.c
+++ b/glib/gbacktrace.c
@@ -57,12 +57,9 @@
 #include <string.h>
 
 #ifdef G_OS_WIN32
-#  define STRICT                /* Strict typing, please */
-#  define _WIN32_WINDOWS 0x0401 /* to get IsDebuggerPresent */
-#  include <windows.h>
-#  undef STRICT
+#include <windows.h>
 #else
-#  include <fcntl.h>
+#include <fcntl.h>
 #endif
 
 #include "gbacktrace.h"
diff --git a/glib/gconvert.c b/glib/gconvert.c
index e0cbdcf5c..6fa5a0ff0 100644
--- a/glib/gconvert.c
+++ b/glib/gconvert.c
@@ -32,13 +32,8 @@
 #include <stdlib.h>
 
 #ifdef G_OS_WIN32
-#include "win_iconv.c"
-#endif
-
-#ifdef G_PLATFORM_WIN32
-#define STRICT
 #include <windows.h>
-#undef STRICT
+#include "win_iconv.c"
 #endif
 
 #include "gconvert.h"
diff --git a/glib/gmain.c b/glib/gmain.c
index 84ecd6102..9de145340 100644
--- a/glib/gmain.c
+++ b/glib/gmain.c
@@ -96,9 +96,8 @@
 #endif  /* HAVE_PIDFD */
 
 #ifdef G_OS_WIN32
-#define STRICT
 #include <windows.h>
-#endif /* G_OS_WIN32 */
+#endif
 
 #ifdef HAVE_MACH_MACH_TIME_H
 #include <mach/mach_time.h>
diff --git a/glib/gpoll.c b/glib/gpoll.c
index cbbbe8886..44c1167cc 100644
--- a/glib/gpoll.c
+++ b/glib/gpoll.c
@@ -72,7 +72,6 @@
 #include <errno.h>
 
 #ifdef G_OS_WIN32
-#define STRICT
 #include <windows.h>
 #include <process.h>
 #endif /* G_OS_WIN32 */
diff --git a/glib/gtimezone.c b/glib/gtimezone.c
index 2b7ed7b85..b8eaf25d9 100644
--- a/glib/gtimezone.c
+++ b/glib/gtimezone.c
@@ -46,8 +46,6 @@
 #endif
 
 #ifdef G_OS_WIN32
-
-#define STRICT
 #include <windows.h>
 #include <wchar.h>
 #endif
diff --git a/glib/gutf8.c b/glib/gutf8.c
index 3aeca3d2f..f54a0a2be 100644
--- a/glib/gutf8.c
+++ b/glib/gutf8.c
@@ -30,9 +30,7 @@
 
 #ifdef G_PLATFORM_WIN32
 #include <stdio.h>
-#define STRICT
 #include <windows.h>
-#undef STRICT
 #endif
 
 #include "gconvert.h"
diff --git a/glib/gwin32.c b/glib/gwin32.c
index d45f2464e..bbee611d3 100644
--- a/glib/gwin32.c
+++ b/glib/gwin32.c
@@ -41,10 +41,8 @@
 #include <errno.h>
 #include <fcntl.h>
 
-#define STRICT			/* Strict typing, please */
 #include <winsock2.h>
 #include <windows.h>
-#undef STRICT
 #ifndef G_WITH_CYGWIN
 #include <direct.h>
 #endif
diff --git a/glib/tests/io-channel-basic.c b/glib/tests/io-channel-basic.c
index 695df6dad..78985e420 100644
--- a/glib/tests/io-channel-basic.c
+++ b/glib/tests/io-channel-basic.c
@@ -36,7 +36,6 @@
   #include <io.h>
   #include <fcntl.h>
   #include <process.h>
-  #define STRICT
   #include <windows.h>
   #define pipe(fds) _pipe(fds, 4096, _O_BINARY)
 #endif
diff --git a/glib/win_iconv.c b/glib/win_iconv.c
index 8635c37e3..9d9a91c8d 100644
--- a/glib/win_iconv.c
+++ b/glib/win_iconv.c
@@ -24,7 +24,10 @@
 # define WINVER 0x0500
 #endif
 
-#define STRICT
+#ifndef STRICT
+# define STRICT
+#endif
+
 #include <windows.h>
 #include <errno.h>
 #include <string.h>