From 14c0eff67c28b3adafbb9a98424eec4a2714e0bb Mon Sep 17 00:00:00 2001 From: Bruno Haible Date: Mon, 10 Oct 2011 02:29:53 +0200 Subject: [PATCH] rint: Determine RINT_LIBM correctly on AIX 7. * m4/mathfunc.m4 (gl_MATHFUNC): Try to invoke the function also directly, not only through a function pointer. Also accept an optional 4th argument with extra code. * m4/rint.m4 (gl_FUNC_RINT): Pass an extra code that gets turned into a rintf() call by gcc when optimizing. --- ChangeLog | 7 +++++++ m4/mathfunc.m4 | 29 +++++++++++++++++++++-------- m4/rint.m4 | 8 ++++++-- 3 files changed, 34 insertions(+), 10 deletions(-) diff --git a/ChangeLog b/ChangeLog index d9419d250..44f1e18dc 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,12 @@ 2011-10-09 Bruno Haible + rint: Determine RINT_LIBM correctly on AIX 7. + * m4/mathfunc.m4 (gl_MATHFUNC): Try to invoke the function also + directly, not only through a function pointer. Also accept an optional + 4th argument with extra code. + * m4/rint.m4 (gl_FUNC_RINT): Pass an extra code that gets turned into a + rintf() call by gcc when optimizing. + mathfunc.m4: Refactor. * m4/mathfunc.m4 (gl_MATHFUNC): Assign the argument list to a temporary m4 variable. diff --git a/m4/mathfunc.m4 b/m4/mathfunc.m4 index 698e18851..b7a1239f7 100644 --- a/m4/mathfunc.m4 +++ b/m4/mathfunc.m4 @@ -1,11 +1,11 @@ -# mathfunc.m4 serial 8 +# mathfunc.m4 serial 9 dnl Copyright (C) 2010-2011 Free Software Foundation, Inc. dnl This file is free software; the Free Software Foundation dnl gives unlimited permission to copy and/or distribute it, dnl with or without modifications, as long as this notice is preserved. -# gl_MATHFUNC(FUNC, RETTYPE, PARAMTYPES) -# -------------------------------------------------- +# gl_MATHFUNC(FUNC, RETTYPE, PARAMTYPES [, EXTRA-CODE]) +# ----------------------------------------------------- # tests whether the function FUNC is available in libc or libm. # RETTYPE is the return type. PARAMTYPES is a parameter list, with parentheses. # It sets FUNC_LIBM to empty or "-lm" accordingly. @@ -13,9 +13,20 @@ dnl with or without modifications, as long as this notice is preserved. AC_DEFUN([gl_MATHFUNC], [ dnl We need the RETTYPE and PARAMTYPES in order to force linking with the - dnl function. With gcc >= 4.3 on glibc/x86_64, calls to the 'fabs' function - dnl are inlined by the compiler, therefore linking of these calls does not - dnl require -lm, but taking the function pointer of 'fabs' does. + dnl function. + dnl 1) With gcc >= 4.3 on glibc/x86_64, calls to the 'fabs' function + dnl are inlined by the compiler, therefore linking of these calls does + dnl not require -lm, but taking the function pointer of 'fabs' does. + dnl 2) On MSVC 9, many math functions exist only as macros with arguments, + dnl whereas the function pointer is undefined. + dnl On the other hand, taking just the function pointer is not enough. + dnl 1) On AIX 7.1, when 'long double' is 128 bit large ("xlc -qldbl128" or + dnl "xlc -qlongdouble" or "gcc -mlong-double-128") many math functions + dnl exist as macros with arguments, that may reference libm or even + dnl completely undefined functions such as __rint128. + dnl 2) In AIX 7.1 with gcc 4.2, when optimization is turned on, calls to + dnl rint() with simple arguments are turned into rintf() calls by the + dnl compiler. But while rint() is resides in libc, rintf() is in libm. m4_pushdef([func], [$1]) m4_pushdef([FUNC], [m4_translit([$1],[abcdefghijklmnopqrstuvwxyz], [ABCDEFGHIJKLMNOPQRSTUVWXYZ])]) @@ -51,7 +62,8 @@ AC_DEFUN([gl_MATHFUNC], float f_ret; double d_ret; long double l_ret;]], - [[$2 y = funcptr ]ARGS[; + [[$2 y = funcptr ]ARGS[ + ]func[ ]ARGS[; + $4 return y < 0.3 || y > 1.7; ]])], [gl_cv_func_]func[_no_libm=yes], @@ -74,7 +86,8 @@ AC_DEFUN([gl_MATHFUNC], float f_ret; double d_ret; long double l_ret;]], - [[$2 y = funcptr ]ARGS[; + [[$2 y = funcptr ]ARGS[ + ]func[ ]ARGS[; + $4 return y < 0.3 || y > 1.7; ]])], [gl_cv_func_]func[_in_libm=yes], diff --git a/m4/rint.m4 b/m4/rint.m4 index 5d9e832e1..2a0913659 100644 --- a/m4/rint.m4 +++ b/m4/rint.m4 @@ -1,4 +1,4 @@ -# rint.m4 serial 2 +# rint.m4 serial 3 dnl Copyright (C) 2011 Free Software Foundation, Inc. dnl This file is free software; the Free Software Foundation dnl gives unlimited permission to copy and/or distribute it, @@ -9,7 +9,11 @@ AC_DEFUN([gl_FUNC_RINT], AC_REQUIRE([gl_MATH_H_DEFAULTS]) dnl Determine RINT_LIBM. - gl_MATHFUNC([rint], [double], [(double)]) + dnl The reason for the extra code is: + dnl In AIX 7.1 with gcc 4.2, when optimization is turned on, calls to + dnl rint() with simple arguments are turned into rintf() calls by the + dnl compiler. But while rint() is resides in libc, rintf() is in libm. + gl_MATHFUNC([rint], [double], [(double)], [y += rint (2.0);]) if test $gl_cv_func_rint_no_libm = no \ && test $gl_cv_func_rint_in_libm = no; then HAVE_RINT=0 -- 2.11.0