From: Taylor R Campbell <campbell@mumble.net>
Date: Fri, 6 Aug 2010 01:15:30 +0000 (+0000)
Subject: Emulate C99 fenv.h with BSD ieeefp.h if necessary.
X-Git-Tag: 20101212-Gtk~120
X-Git-Url: https://birchwood-abbey.net/git?a=commitdiff_plain;h=e3c57874125b713f87465c7aa339fcab37009fa7;p=mit-scheme.git

Emulate C99 fenv.h with BSD ieeefp.h if necessary.
---

diff --git a/src/microcode/configure.ac b/src/microcode/configure.ac
index a3e22029e..7f930cfda 100644
--- a/src/microcode/configure.ac
+++ b/src/microcode/configure.ac
@@ -402,7 +402,8 @@ AC_HEADER_STDC
 AC_HEADER_STDBOOL
 AC_HEADER_SYS_WAIT
 AC_HEADER_TIME
-AC_CHECK_HEADERS([bsdtty.h fcntl.h fenv.h limits.h malloc.h sgtty.h stropts.h time.h])
+AC_CHECK_HEADERS([bsdtty.h fcntl.h fenv.h ieeefp.h limits.h malloc.h sgtty.h])
+AC_CHECK_HEADERS([stropts.h time.h])
 AC_CHECK_HEADERS([sys/file.h sys/ioctl.h sys/mount.h sys/param.h sys/poll.h])
 AC_CHECK_HEADERS([sys/ptyio.h sys/socket.h sys/time.h sys/un.h sys/vfs.h])
 AC_CHECK_HEADERS([termio.h termios.h unistd.h utime.h])
@@ -650,7 +651,7 @@ AC_FUNC_WAIT3
 AC_CHECK_FUNCS([ctermid])
 AC_CHECK_FUNCS([dup2])
 AC_CHECK_FUNCS([fcntl fdatasync fegetround fesetround floor fpathconf frexp])
-AC_CHECK_FUNCS([fsync fsync_range ftruncate])
+AC_CHECK_FUNCS([fpgetround fpsetround fsync fsync_range ftruncate])
 AC_CHECK_FUNCS([getcwd gethostbyname gethostname getlogin getpagesize getpgrp])
 AC_CHECK_FUNCS([getpt gettimeofday getwd grantpt])
 AC_CHECK_FUNCS([kill])
diff --git a/src/microcode/sysprim.c b/src/microcode/sysprim.c
index 1d1cc592f..7654116bf 100644
--- a/src/microcode/sysprim.c
+++ b/src/microcode/sysprim.c
@@ -205,6 +205,48 @@ DEFINE_PRIMITIVE ("CC-BLOCK-LINKAGE-INFO", Prim_cc_block_linkage_info, 1, 1, 0)
   PRIMITIVE_RETURN (cc_block_linkage_info (ARG_REF (1)));
 }
 
+/* Emulate <fenv.h> with BSD's <ieeefp.h>.  */
+
+#if !defined(HAVE_FENV_H) && defined(HAVE_IEEEFP_H)
+#  include <ieeefp.h>
+#endif
+
+#if !defined(HAVE_FEGETROUND) && defined(HAVE_FPGETROUND)
+#  define fegetround fpgetround
+#  define HAVE_FEGETROUND
+#endif
+
+#if !defined(HAVE_FESETROUND) && defined(HAVE_FPSETROUND)
+
+static inline int
+fesetround (int mode)
+{
+  /* fpsetround never fails; instead, it returns the old rounding mode,
+     which has only a one-in-four chance in general of being 0 as the
+     SET-FLOAT-ROUNDING-MODE primitive wants.  */
+  (void) fpsetround (mode);
+  return (0);
+}
+
+#  define HAVE_FESETROUND
+#endif
+
+#if !defined(FE_TONEAREST) && defined(FP_RN)
+#  define FE_TONEAREST FP_RN
+#endif
+
+#if !defined(FE_TOWARDZERO) && defined(FP_RZ)
+#  define FE_TOWARDZERO FP_RZ
+#endif
+
+#if !defined(FE_DOWNWARD) && defined(FP_RM)
+#  define FE_DOWNWARD FP_RM
+#endif
+
+#if !defined(FE_UPWARD) && defined(FP_RP)
+#  define FE_UPWARD FP_RP
+#endif
+
 #ifndef __GNUC__
 #  pragma STDC FENV_ACCESS ON
 #endif