| 1 | # log1p.m4 serial 3 |
| 2 | dnl Copyright (C) 2012-2013 Free Software Foundation, Inc. |
| 3 | dnl This file is free software; the Free Software Foundation |
| 4 | dnl gives unlimited permission to copy and/or distribute it, |
| 5 | dnl with or without modifications, as long as this notice is preserved. |
| 6 | |
| 7 | AC_DEFUN([gl_FUNC_LOG1P], |
| 8 | [ |
| 9 | m4_divert_text([DEFAULTS], [gl_log1p_required=plain]) |
| 10 | AC_REQUIRE([gl_MATH_H_DEFAULTS]) |
| 11 | |
| 12 | dnl Persuade glibc <math.h> to declare log1p(). |
| 13 | AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS]) |
| 14 | |
| 15 | dnl Determine LOG1P_LIBM. |
| 16 | gl_COMMON_DOUBLE_MATHFUNC([log1p]) |
| 17 | |
| 18 | dnl Test whether log1p() exists. |
| 19 | save_LIBS="$LIBS" |
| 20 | LIBS="$LIBS $LOG1P_LIBM" |
| 21 | AC_CHECK_FUNCS([log1p]) |
| 22 | LIBS="$save_LIBS" |
| 23 | if test $ac_cv_func_log1p = yes; then |
| 24 | : |
| 25 | m4_ifdef([gl_FUNC_LOG1P_IEEE], [ |
| 26 | if test $gl_log1p_required = ieee && test $REPLACE_LOG1P = 0; then |
| 27 | AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles |
| 28 | AC_CACHE_CHECK([whether log1p works according to ISO C 99 with IEC 60559], |
| 29 | [gl_cv_func_log1p_ieee], |
| 30 | [ |
| 31 | save_LIBS="$LIBS" |
| 32 | LIBS="$LIBS $LOG1P_LIBM" |
| 33 | AC_RUN_IFELSE( |
| 34 | [AC_LANG_SOURCE([[ |
| 35 | #ifndef __NO_MATH_INLINES |
| 36 | # define __NO_MATH_INLINES 1 /* for glibc */ |
| 37 | #endif |
| 38 | #include <math.h> |
| 39 | ]gl_DOUBLE_MINUS_ZERO_CODE[ |
| 40 | ]gl_DOUBLE_SIGNBIT_CODE[ |
| 41 | static double dummy (double x) { return 0; } |
| 42 | int main (int argc, char *argv[]) |
| 43 | { |
| 44 | double (*my_log1p) (double) = argc ? log1p : dummy; |
| 45 | /* This test fails on AIX, HP-UX 11. */ |
| 46 | double y = my_log1p (minus_zerod); |
| 47 | if (!(y == 0.0) || (signbitd (minus_zerod) && !signbitd (y))) |
| 48 | return 1; |
| 49 | return 0; |
| 50 | } |
| 51 | ]])], |
| 52 | [gl_cv_func_log1p_ieee=yes], |
| 53 | [gl_cv_func_log1p_ieee=no], |
| 54 | [case "$host_os" in |
| 55 | # Guess yes on glibc systems. |
| 56 | *-gnu*) gl_cv_func_log1p_ieee="guessing yes" ;; |
| 57 | # If we don't know, assume the worst. |
| 58 | *) gl_cv_func_log1p_ieee="guessing no" ;; |
| 59 | esac |
| 60 | ]) |
| 61 | LIBS="$save_LIBS" |
| 62 | ]) |
| 63 | case "$gl_cv_func_log1p_ieee" in |
| 64 | *yes) ;; |
| 65 | *) REPLACE_LOG1P=1 ;; |
| 66 | esac |
| 67 | fi |
| 68 | ]) |
| 69 | else |
| 70 | HAVE_LOG1P=0 |
| 71 | fi |
| 72 | if test $HAVE_LOG1P = 0 || test $REPLACE_LOG1P = 1; then |
| 73 | dnl Find libraries needed to link lib/log1p.c. |
| 74 | AC_REQUIRE([gl_FUNC_ISNAND]) |
| 75 | AC_REQUIRE([gl_FUNC_LOG]) |
| 76 | AC_REQUIRE([gl_FUNC_ROUND]) |
| 77 | LOG1P_LIBM= |
| 78 | dnl Append $ISNAND_LIBM to LOG1P_LIBM, avoiding gratuitous duplicates. |
| 79 | case " $LOG1P_LIBM " in |
| 80 | *" $ISNAND_LIBM "*) ;; |
| 81 | *) LOG1P_LIBM="$LOG1P_LIBM $ISNAND_LIBM" ;; |
| 82 | esac |
| 83 | dnl Append $LOG_LIBM to LOG1P_LIBM, avoiding gratuitous duplicates. |
| 84 | case " $LOG1P_LIBM " in |
| 85 | *" $LOG_LIBM "*) ;; |
| 86 | *) LOG1P_LIBM="$LOG1P_LIBM $LOG_LIBM" ;; |
| 87 | esac |
| 88 | dnl Append $ROUND_LIBM to LOG1P_LIBM, avoiding gratuitous duplicates. |
| 89 | case " $LOG1P_LIBM " in |
| 90 | *" $ROUND_LIBM "*) ;; |
| 91 | *) LOG1P_LIBM="$LOG1P_LIBM $ROUND_LIBM" ;; |
| 92 | esac |
| 93 | fi |
| 94 | ]) |