package/jamvm/0001-Use-fenv.h-when-available-instead-of-fpu_control.h.patch

   1 From ecd4eceae98cfb1c83133bdeaa9095546ca8b7c6 Mon Sep 17 00:00:00 2001
   2 From: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
   3 Date: Thu, 26 May 2016 15:05:48 +0200
   4 Subject: [PATCH] Use <fenv.h> when available instead of <fpu_control.h>
   5
   6 musl libc (http://musl-libc.org lack the non-standard <fpu_control.h>
   7 header, which is used in src/os/linux/{i386,x86_64}/init.c files to
   8 setup the floating point precision. This patch makes it use the
   9 standard C <fenv.h> header instead when available.
  10
  11 Original patch at Felix Janda at
  12 https://sourceforge.net/p/jamvm/patches/6/, adapted to still use
  13 <fpu_control.h> if <fenv.h> is not provided.
  14
  15 Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
  16 ---
  17  configure.ac               |  2 +-
  18  src/os/linux/i386/init.c   | 15 +++++++++++++++
  19  src/os/linux/x86_64/init.c | 15 +++++++++++++--
  20  3 files changed, 29 insertions(+), 3 deletions(-)
  21
  22 diff --git a/configure.ac b/configure.ac
  23 index 19f77e6..ce59a3e 100644
  24 --- a/configure.ac
  25 +++ b/configure.ac
  26 @@ -279,7 +279,7 @@ fi
  27
  28  dnl Checks for header files.
  29  AC_HEADER_STDC
  30 -AC_CHECK_HEADERS(sys/time.h unistd.h endian.h sys/param.h locale.h alloca.h)
  31 +AC_CHECK_HEADERS(sys/time.h unistd.h endian.h sys/param.h locale.h alloca.h fenv.h)
  32
  33  if test "$enable_zip" != no; then
  34      AC_CHECK_HEADER(zlib.h,,AC_MSG_ERROR(zlib.h is missing))
  35 diff --git a/src/os/linux/i386/init.c b/src/os/linux/i386/init.c
  36 index d9c6648..8fefe7d 100644
  37 --- a/src/os/linux/i386/init.c
  38 +++ b/src/os/linux/i386/init.c
  39 @@ -19,18 +19,33 @@
  40   * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  41   */
  42
  43 +#include "config.h"
  44 +
  45 +#if defined(HAVE_FENV_H)
  46 +#include <fenv.h>
  47 +#else
  48  #include <fpu_control.h>
  49 +#endif
  50
  51  /* Change floating point precision to double (64-bit) from
  52   * the extended (80-bit) Linux default. */
  53
  54  void setDoublePrecision() {
  55 +#if defined(HAVE_FENV_H)
  56 +    fenv_t fenv;
  57 +
  58 +    fegetenv(&fenv);
  59 +    fenv.__control_word &= ~0x300; /* _FPU_EXTENDED */
  60 +    fenv.__control_word |= 0x200; /* _FPU_DOUBLE */
  61 +    fesetenv(&fenv);
  62 +#else
  63      fpu_control_t cw;
  64
  65      _FPU_GETCW(cw);
  66      cw &= ~_FPU_EXTENDED;
  67      cw |= _FPU_DOUBLE;
  68      _FPU_SETCW(cw);
  69 +#endif
  70  }
  71
  72  void initialisePlatform() {
  73 diff --git a/src/os/linux/x86_64/init.c b/src/os/linux/x86_64/init.c
  74 index 9d55229..b42b14e 100644
  75 --- a/src/os/linux/x86_64/init.c
  76 +++ b/src/os/linux/x86_64/init.c
  77 @@ -19,7 +19,11 @@
  78   * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  79   */
  80
  81 -#ifdef __linux__
  82 +#include "config.h"
  83 +
  84 +#if defined(HAVE_FENV_H)
  85 +#include <fenv.h>
  86 +#else
  87  #include <fpu_control.h>
  88  #endif
  89
  90 @@ -30,7 +34,14 @@
  91  */
  92
  93  void setDoublePrecision() {
  94 -#ifdef __linux__
  95 +#if defined(HAVE_FENV_H)
  96 +    fenv_t fenv;
  97 +
  98 +    fegetenv(&fenv);
  99 +    fenv.__control_word &= ~0x300; /*_FPU_EXTENDED */
 100 +    fenv.__control_word |= 0x200; /*_FPU_DOUBLE */
 101 +    fesetenv(&fenv);
 102 +#else
 103      fpu_control_t cw;
 104
 105      _FPU_GETCW(cw);
 106 --
 107 2.7.4
 108