diff --git a/src/backend/port/bsdi/Makefile.inc b/src/backend/port/bsdi/Makefile.inc
index 96eb2c5fc4..347ded2c66 100644
--- a/src/backend/port/bsdi/Makefile.inc
+++ b/src/backend/port/bsdi/Makefile.inc
@@ -10,6 +10,5 @@
 #
 #-------------------------------------------------------------------------
 
-CFLAGS+=-DUSE_POSIX_TIME -DNEED_CBRT
 LDADD+= -ldld -lipc
 SUBSRCS= dynloader.c
diff --git a/src/backend/port/bsdi_2_1/Makefile.inc b/src/backend/port/bsdi_2_1/Makefile.inc
index a5592e18d4..cb9bd71e88 100644
--- a/src/backend/port/bsdi_2_1/Makefile.inc
+++ b/src/backend/port/bsdi_2_1/Makefile.inc
@@ -10,5 +10,4 @@
 #
 #-------------------------------------------------------------------------
 
-CFLAGS+=-DUSE_POSIX_TIME -DNEED_CBRT
 LDADD+= -ldl -lipc
diff --git a/src/backend/port/dgux/Makefile.inc b/src/backend/port/dgux/Makefile.inc
index 407e440b3d..b735b8a630 100644
--- a/src/backend/port/dgux/Makefile.inc
+++ b/src/backend/port/dgux/Makefile.inc
@@ -7,7 +7,7 @@
 #
 #
 # IDENTIFICATION
-#    $Header: /cvsroot/pgsql/src/backend/port/dgux/Attic/Makefile.inc,v 1.1 1996/07/25 20:43:56 scrappy Exp $
+#    $Header: /cvsroot/pgsql/src/backend/port/dgux/Attic/Makefile.inc,v 1.2 1996/10/18 00:33:14 scrappy Exp $
 #
 # NOTES
 #    The Linux port is included here by courtesy of Kai Petzke.
@@ -21,5 +21,3 @@ BIGOBJS= false
 CFLAGS+= -DLINUX_ELF
 
 HEADERS+= machine.h port-protos.h
-CFLAGS+= #-DNEED_CBRT
-
diff --git a/src/backend/port/hpux/Makefile.inc b/src/backend/port/hpux/Makefile.inc
index 4ff60d2019..af33802011 100644
--- a/src/backend/port/hpux/Makefile.inc
+++ b/src/backend/port/hpux/Makefile.inc
@@ -7,7 +7,7 @@
 #
 #
 # IDENTIFICATION
-#    $Header: /cvsroot/pgsql/src/backend/port/hpux/Attic/Makefile.inc,v 1.1.1.1 1996/07/09 06:21:43 scrappy Exp $
+#    $Header: /cvsroot/pgsql/src/backend/port/hpux/Attic/Makefile.inc,v 1.2 1996/10/18 00:33:22 scrappy Exp $
 #
 #-------------------------------------------------------------------------
 
@@ -29,15 +29,6 @@ LDADD+= -ll /usr/lib/libdld.sl
 endif
 endif
 
-CFLAGS+= -DUSE_POSIX_TIME
-
-#
-# cbrt(3m) and rint(3m) are missing from 8.07.
-# cbrt(3m) and rint(3m) are broken in 9.01.
-# cbrt(3m) seems to be missing on 9.00 even though it is documented.
-#
-CFLAGS+= -DNEED_RINT -DNEED_CBRT
-
 #
 # The #pragma trick required on 8.07 no longer works -- the #pragma
 # is thoroughly broken.  However, the +u flag has been extended to
diff --git a/src/backend/port/linux/Makefile.inc b/src/backend/port/linux/Makefile.inc
index cc35929a26..00ed140f3b 100644
--- a/src/backend/port/linux/Makefile.inc
+++ b/src/backend/port/linux/Makefile.inc
@@ -7,7 +7,7 @@
 #
 #
 # IDENTIFICATION
-#    $Header: /cvsroot/pgsql/src/backend/port/linux/Attic/Makefile.inc,v 1.1.1.1 1996/07/09 06:21:44 scrappy Exp $
+#    $Header: /cvsroot/pgsql/src/backend/port/linux/Attic/Makefile.inc,v 1.2 1996/10/18 00:33:32 scrappy Exp $
 #
 # NOTES
 #    The Linux port is included here by courtesy of Kai Petzke.
@@ -32,5 +32,3 @@ SUBSRCS+= dynloader.c
 endif
 
 HEADERS+= machine.h port-protos.h
-CFLAGS+= -DNEED_CBRT
-
diff --git a/src/backend/port/win32/nt.h b/src/backend/port/win32/nt.h
index abe3519ab5..a879e37f16 100644
--- a/src/backend/port/win32/nt.h
+++ b/src/backend/port/win32/nt.h
@@ -46,9 +46,5 @@ struct sembuf
 #define GETNCNT 5
 #define GETVAL 6
 
-/* for float.c */
-#define NEED_CBRT
-#define NEED_ISINF
-
 #define POSTGRESDIR "d:\\pglite"
 #define PGDATADIR "d:\\pglite\\data"
diff --git a/src/include/config.h b/src/include/config.h
index 0ddfe7feab..9a849ff6e0 100644
--- a/src/include/config.h
+++ b/src/include/config.h
@@ -8,8 +8,28 @@
 
 #define BLCKSZ	8192
 
+#if defined(sequent) || \
+    defined(PORTNAME_aix) || \
+    defined(PORTNAME_alpha) || \
+    defined(PORTNAME_bsdi) || \
+    defined(PORTNAME_hpux) || \
+    defined(PORTNAME_dgux) || \
+    defined(PORTNAME_i386_solaris) || \
+    defined(PORTNAME_sparc_solaris) || \
+    defined(PORTNAME_ultrix4) || \
+    defined(PORTNAME_svr4)
+#define NEED_UNION_SEMUN 
+#endif
+
+#if defined(linux)
+#  define NEED_CBRT
+#endif
+
 #if defined(hpux)
+#  define USE_POSIX_TIME
 #  define HAVE_TZSET
+#  define NEED_CBRT
+#  define NEED_RINT
 #endif
 
 #if defined(i386_solaris) 
@@ -31,13 +51,16 @@
 #  define NOFILE	100
 #  define NEED_UNION_SEMUN
 #  define HAVE_TZSET
+#  define NEED_CBRT
+#  define NEED_ISINF
 #endif /* WIN32 */
 
-#if defined(__FreeBSD__) || \
-    defined(__NetBSD__) || \
-    defined(bsdi)
+#if defined(BSD44_derived) || \
+    defined(bsdi) || \
+    defined(bsdi_2_1)
 #  define USE_LIMITS_H
 #  define USE_POSIX_TIME
+#  define NEED_CBRT
 #endif
 
 #if defined(aix)
@@ -94,18 +117,6 @@
  * long locks.  For some reason union semun is never defined in the
  * System V header files so we must do it ourselves.
  */
-#if defined(sequent) || \
-    defined(PORTNAME_aix) || \
-    defined(PORTNAME_alpha) || \
-    defined(PORTNAME_bsdi) || \
-    defined(PORTNAME_hpux) || \
-    defined(PORTNAME_dgux) || \
-    defined(PORTNAME_i386_solaris) || \
-    defined(PORTNAME_sparc_solaris) || \
-    defined(PORTNAME_ultrix4) || \
-    defined(PORTNAME_svr4)
-#define NEED_UNION_SEMUN 
-#endif
 
 /*  Debug and various "defines" that should be documented */