diff --git a/posix.cc b/posix.cc
index 945c796c..870cb848 100644
--- a/posix.cc
+++ b/posix.cc
@@ -55,6 +55,9 @@
 
 # ifdef __MINGW32__
 #  define _SH_DENYNO 0x40
+#  undef fileno
+# endif
+
 # endif
 
 #endif  // _WIN32
diff --git a/posix.h b/posix.h
index 16cf952a..5acf64c6 100644
--- a/posix.h
+++ b/posix.h
@@ -61,7 +61,7 @@
 # define FMT_SYSTEM(call) call
 # ifdef _WIN32
 // Fix warnings about deprecated symbols.
-#  define FMT_POSIX_CALL(call) (::_##call)
+#  define FMT_POSIX_CALL(call) ::_##call
 # else
 #  define FMT_POSIX_CALL(call) ::call
 # endif