[PATCH 5/5] libm: Control errno support with _IEEE_LIBM configuration parameter
Corinna Vinschen
vinschen@redhat.com
Wed Aug 5 07:41:40 GMT 2020
On Aug 4 15:22, Keith Packard via Newlib wrote:
> This removes the run-time configuration of errno support present in
> portions of the math library and unifies all of the compile-time errno
> configuration under a single parameter so that the whole library
> is consistent.
>
> The run-time support provided by _LIB_VERSION is no longer present in
> the public API, although it is still used internally to disable errno
> setting in some functions. Now that it is a constant, the compiler should
> remove that code when errno is not supported.
>
> This removes s_lib_ver.c as _LIB_VERSION is no longer variable.
This math stuff is a bit over my head. IIUC, the default is
NOT setting _IEEE_LIBM, which results in the defauklt behaviour
today. That's what I care most about: Not introducing backward
incompatible settings into Cygwin.
Corinna
>
> Signed-off-by: Keith Packard <keithp@keithp.com>
> ---
> newlib/libc/include/math.h | 16 ---------------
> newlib/libm/common/Makefile.am | 2 +-
> newlib/libm/common/Makefile.in | 11 ++--------
> newlib/libm/common/fdlibm.h | 1 +
> newlib/libm/common/math_config.h | 5 +++++
> newlib/libm/common/s_lib_ver.c | 35 --------------------------------
> 6 files changed, 9 insertions(+), 61 deletions(-)
> delete mode 100644 newlib/libm/common/s_lib_ver.c
>
> diff --git a/newlib/libc/include/math.h b/newlib/libc/include/math.h
> index 9fd82d9fa..5e6155cc4 100644
> --- a/newlib/libc/include/math.h
> +++ b/newlib/libc/include/math.h
> @@ -612,22 +612,6 @@ extern int *__signgam (void);
> #define M_LOG2_E _M_LN2
> #define M_INVLN2 1.4426950408889633870E0 /* 1 / log(2) */
>
> -/* Global control over fdlibm error handling. */
> -
> -enum __fdlibm_version
> -{
> - __fdlibm_ieee = -1,
> - __fdlibm_posix
> -};
> -
> -#define _LIB_VERSION_TYPE enum __fdlibm_version
> -#define _LIB_VERSION __fdlib_version
> -
> -extern __IMPORT _LIB_VERSION_TYPE _LIB_VERSION;
> -
> -#define _IEEE_ __fdlibm_ieee
> -#define _POSIX_ __fdlibm_posix
> -
> #endif /* __BSD_VISIBLE */
>
> _END_STD_C
> diff --git a/newlib/libm/common/Makefile.am b/newlib/libm/common/Makefile.am
> index 1eef0236a..1d178da4d 100644
> --- a/newlib/libm/common/Makefile.am
> +++ b/newlib/libm/common/Makefile.am
> @@ -8,7 +8,7 @@ src = s_finite.c s_copysign.c s_modf.c s_scalbn.c \
> s_cbrt.c s_exp10.c s_expm1.c s_ilogb.c \
> s_infinity.c s_isinf.c s_isinfd.c s_isnan.c s_isnand.c \
> s_log1p.c s_nan.c s_nextafter.c s_pow10.c \
> - s_rint.c s_logb.c s_log2.c s_lib_ver.c \
> + s_rint.c s_logb.c s_log2.c \
> s_fdim.c s_fma.c s_fmax.c s_fmin.c s_fpclassify.c \
> s_lrint.c s_llrint.c \
> s_lround.c s_llround.c s_nearbyint.c s_remquo.c s_round.c s_scalbln.c \
> diff --git a/newlib/libm/common/Makefile.in b/newlib/libm/common/Makefile.in
> index 2caf7dd6c..b1098565f 100644
> --- a/newlib/libm/common/Makefile.in
> +++ b/newlib/libm/common/Makefile.in
> @@ -85,7 +85,6 @@ am__objects_1 = lib_a-s_finite.$(OBJEXT) lib_a-s_copysign.$(OBJEXT) \
> lib_a-s_nan.$(OBJEXT) lib_a-s_nextafter.$(OBJEXT) \
> lib_a-s_pow10.$(OBJEXT) lib_a-s_rint.$(OBJEXT) \
> lib_a-s_logb.$(OBJEXT) lib_a-s_log2.$(OBJEXT) \
> - lib_a-s_lib_ver.$(OBJEXT) lib_a-s_fdim.$(OBJEXT) \
> lib_a-s_fma.$(OBJEXT) lib_a-s_fmax.$(OBJEXT) \
> lib_a-s_fmin.$(OBJEXT) lib_a-s_fpclassify.$(OBJEXT) \
> lib_a-s_lrint.$(OBJEXT) lib_a-s_llrint.$(OBJEXT) \
> @@ -163,7 +162,7 @@ am__objects_5 = s_finite.lo s_copysign.lo s_modf.lo s_scalbn.lo \
> s_cbrt.lo s_exp10.lo s_expm1.lo s_ilogb.lo s_infinity.lo \
> s_isinf.lo s_isinfd.lo s_isnan.lo s_isnand.lo s_log1p.lo \
> s_nan.lo s_nextafter.lo s_pow10.lo s_rint.lo s_logb.lo \
> - s_log2.lo s_lib_ver.lo s_fdim.lo s_fma.lo s_fmax.lo s_fmin.lo \
> + s_log2.lo s_fdim.lo s_fma.lo s_fmax.lo s_fmin.lo \
> s_fpclassify.lo s_lrint.lo s_llrint.lo s_lround.lo \
> s_llround.lo s_nearbyint.lo s_remquo.lo s_round.lo \
> s_scalbln.lo s_signbit.lo s_trunc.lo exp.lo exp2.lo \
> @@ -354,7 +353,7 @@ src = s_finite.c s_copysign.c s_modf.c s_scalbn.c \
> s_cbrt.c s_exp10.c s_expm1.c s_ilogb.c \
> s_infinity.c s_isinf.c s_isinfd.c s_isnan.c s_isnand.c \
> s_log1p.c s_nan.c s_nextafter.c s_pow10.c \
> - s_rint.c s_logb.c s_log2.c s_lib_ver.c \
> + s_rint.c s_logb.c s_log2.c \
> s_fdim.c s_fma.c s_fmax.c s_fmin.c s_fpclassify.c \
> s_lrint.c s_llrint.c \
> s_lround.c s_llround.c s_nearbyint.c s_remquo.c s_round.c s_scalbln.c \
> @@ -602,12 +601,6 @@ lib_a-s_log2.o: s_log2.c
> lib_a-s_log2.obj: s_log2.c
> $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CFLAGS) $(CFLAGS) -c -o lib_a-s_log2.obj `if test -f 's_log2.c'; then $(CYGPATH_W) 's_log2.c'; else $(CYGPATH_W) '$(srcdir)/s_log2.c'; fi`
>
> -lib_a-s_lib_ver.o: s_lib_ver.c
> - $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CFLAGS) $(CFLAGS) -c -o lib_a-s_lib_ver.o `test -f 's_lib_ver.c' || echo '$(srcdir)/'`s_lib_ver.c
> -
> -lib_a-s_lib_ver.obj: s_lib_ver.c
> - $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CFLAGS) $(CFLAGS) -c -o lib_a-s_lib_ver.obj `if test -f 's_lib_ver.c'; then $(CYGPATH_W) 's_lib_ver.c'; else $(CYGPATH_W) '$(srcdir)/s_lib_ver.c'; fi`
> -
> lib_a-s_fdim.o: s_fdim.c
> $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(lib_a_CFLAGS) $(CFLAGS) -c -o lib_a-s_fdim.o `test -f 's_fdim.c' || echo '$(srcdir)/'`s_fdim.c
>
> diff --git a/newlib/libm/common/fdlibm.h b/newlib/libm/common/fdlibm.h
> index 8dfff243d..8dffc832d 100644
> --- a/newlib/libm/common/fdlibm.h
> +++ b/newlib/libm/common/fdlibm.h
> @@ -15,6 +15,7 @@
> #include <math.h>
> #include <sys/types.h>
> #include <machine/ieeefp.h>
> +#include "math_config.h"
>
> /* Most routines need to check whether a float is finite, infinite, or not a
> number, and many need to know whether the result of an operation will
> diff --git a/newlib/libm/common/math_config.h b/newlib/libm/common/math_config.h
> index 3be7e6320..1089b0ec6 100644
> --- a/newlib/libm/common/math_config.h
> +++ b/newlib/libm/common/math_config.h
> @@ -38,15 +38,20 @@
> #endif
> #ifdef _IEEE_LIBM
> # define WANT_ERRNO 0
> +# define _LIB_VERSION _IEEE_
> #else
> /* Set errno according to ISO C with (math_errhandling & MATH_ERRNO) != 0. */
> # define WANT_ERRNO 1
> +# define _LIB_VERSION _POSIX_
> #endif
> #ifndef WANT_ERRNO_UFLOW
> /* Set errno to ERANGE if result underflows to 0 (in all rounding modes). */
> # define WANT_ERRNO_UFLOW (WANT_ROUNDING && WANT_ERRNO)
> #endif
>
> +#define _IEEE_ -1
> +#define _POSIX_ 0
> +
> /* Compiler can inline round as a single instruction. */
> #ifndef HAVE_FAST_ROUND
> # if __aarch64__
> diff --git a/newlib/libm/common/s_lib_ver.c b/newlib/libm/common/s_lib_ver.c
> deleted file mode 100644
> index 8da03b79a..000000000
> --- a/newlib/libm/common/s_lib_ver.c
> +++ /dev/null
> @@ -1,35 +0,0 @@
> -
> -/* @(#)s_lib_ver.c 5.1 93/09/24 */
> -/*
> - * ====================================================
> - * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
> - *
> - * Developed at SunPro, a Sun Microsystems, Inc. business.
> - * Permission to use, copy, modify, and distribute this
> - * software is freely granted, provided that this notice
> - * is preserved.
> - * ====================================================
> - */
> -
> -/*
> - * MACRO for standards
> - */
> -
> -#include "fdlibm.h"
> -
> -/*
> - * define and initialize _LIB_VERSION
> - */
> -#ifdef _POSIX_MODE
> -_LIB_VERSION_TYPE _LIB_VERSION = _POSIX_;
> -#else
> -#ifdef _XOPEN_MODE
> -#error _XOPEN_MODE is unsupported
> -#else
> -#ifdef _SVID3_MODE
> -#error _SVID3_MODE is unsupported
> -#else /* default _IEEE_MODE */
> -_LIB_VERSION_TYPE _LIB_VERSION = _IEEE_;
> -#endif
> -#endif
> -#endif
> --
> 2.28.0
--
Corinna Vinschen
Cygwin Maintainer
Red Hat
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