diff --git a/Modules/_cursesmodule.c b/Modules/_cursesmodule.c
index 092fb69..9b3b8cd 100644
--- a/Modules/_cursesmodule.c
+++ b/Modules/_cursesmodule.c
@@ -105,10 +105,6 @@
 #include "Python.h"
 
 
-#ifdef __osf__
-#define STRICT_SYSV_CURSES      /* Don't use ncurses extensions */
-#endif
-
 #ifdef __hpux
 #define STRICT_SYSV_CURSES
 #endif
diff --git a/Modules/fpectlmodule.c b/Modules/fpectlmodule.c
index 1bb51cf..6af2f82 100644
--- a/Modules/fpectlmodule.c
+++ b/Modules/fpectlmodule.c
@@ -174,17 +174,6 @@
     fp_enable(TRP_INVALID | TRP_DIV_BY_ZERO | TRP_OVERFLOW);
     PyOS_setsig(SIGFPE, handler);
 
-/*-- DEC ALPHA OSF --------------------------------------------------------*/
-#elif defined(__alpha) && defined(__osf__)
-    /* References:   exception_intro, ieee man pages */
-    /* cc -c -I/usr/local/python/include fpectlmodule.c */
-    /* ld -shared -o fpectlmodule.so fpectlmodule.o */
-#include <machine/fpu.h>
-    unsigned long fp_control =
-    IEEE_TRAP_ENABLE_INV | IEEE_TRAP_ENABLE_DZE | IEEE_TRAP_ENABLE_OVF;
-    ieee_set_fp_control(fp_control);
-    PyOS_setsig(SIGFPE, handler);
-
 /*-- DEC ALPHA LINUX ------------------------------------------------------*/
 #elif defined(__alpha) && defined(linux)
 #include <asm/fpu.h>
diff --git a/Modules/mathmodule.c b/Modules/mathmodule.c
index 29c32a3..d173bff 100644
--- a/Modules/mathmodule.c
+++ b/Modules/mathmodule.c
@@ -55,11 +55,6 @@
 #include "Python.h"
 #include "_math.h"
 
-#ifdef _OSF_SOURCE
-/* OSF1 5.1 doesn't make this available with XOPEN_SOURCE_EXTENDED defined */
-extern double copysign(double, double);
-#endif
-
 /*
    sin(pi*x), giving accurate results for all finite x (especially x
    integral or close to an integer).  This is here for use in the
diff --git a/Modules/socketmodule.c b/Modules/socketmodule.c
index 687d964..3658fa2 100644
--- a/Modules/socketmodule.c
+++ b/Modules/socketmodule.c
@@ -155,7 +155,7 @@
 #endif
 
 #ifdef HAVE_GETHOSTBYNAME_R
-# if defined(_AIX) || defined(__osf__)
+# if defined(_AIX)
 #  define HAVE_GETHOSTBYNAME_R_3_ARG
 # elif defined(__sun) || defined(__sgi)
 #  define HAVE_GETHOSTBYNAME_R_5_ARG
diff --git a/Modules/termios.c b/Modules/termios.c
index edeb6f5..b78d33e 100644
--- a/Modules/termios.c
+++ b/Modules/termios.c
@@ -9,11 +9,6 @@
 #endif
 
 #include <termios.h>
-#ifdef __osf__
-/* On OSF, sys/ioctl.h requires that struct termio already be defined,
- * so this needs to be included first on that platform. */
-#include <termio.h>
-#endif
 #include <sys/ioctl.h>
 
 /* HP-UX requires that this be included to pick up MDCD, MCTS, MDSR,