On Jun 16 11:31, Radek Barton wrote: > Hello. > > This is more a question than patch submission: Without the attached changes, > the Cygwin cannot be linked for AArch64 failing on: > ``` > ld: cannot export _fe_nomask_env: symbol not defined > ld: cannot export fedisableexcept: symbol not defined > ld: cannot export fegetexcept: symbol not defined > ld: cannot export fegetprec: symbol not defined > ld: cannot export fesetprec: symbol not defined > ``` > Can anybody share some insights why are those changes needed and whether > there is a better way how to overcome this issue? > > Note that the `feenableexcept`, `fedisableexcept`, `fegetexcept` > implementations are similarly defined in > `newlib/libc/machine/mips/machine/fenv-fp.h` for MIPS architecture as well.
This would be a question for our ARM guys. Richard? Thanks, Corinna > > Thank you, > > Radek > > --- > >From 17fd8e16061ab199d111b303a44c042ea43c4018 Mon Sep 17 00:00:00 2001 > From: Radek Barton <[email protected]> > Date: Mon, 9 Jun 2025 08:55:18 +0200 > Subject: [PATCH/QUESTION] newlib: fenv: AArch64 Cygwin linking fixes > > --- > newlib/libc/machine/aarch64/machine/fenv-fp.h | 64 +++++++++++++++++++ > newlib/libc/machine/aarch64/sys/fenv.h | 40 ------------ > newlib/libm/machine/aarch64/fenv.c | 7 ++ > winsup/cygwin/fenv.c | 10 +++ > 4 files changed, 81 insertions(+), 40 deletions(-) > > diff --git a/newlib/libc/machine/aarch64/machine/fenv-fp.h > b/newlib/libc/machine/aarch64/machine/fenv-fp.h > index d8ec3fc76..e42e2d873 100644 > --- a/newlib/libc/machine/aarch64/machine/fenv-fp.h > +++ b/newlib/libc/machine/aarch64/machine/fenv-fp.h > @@ -154,3 +154,67 @@ feupdateenv(const fenv_t *__envp) > return (0); > } > > +#if __BSD_VISIBLE > + > +/* We currently provide no external definitions of the functions below. */ > + > +__fenv_static inline int > +feenableexcept(int __mask) > +{ > + fenv_t __old_r, __new_r; > + > + __mrs_fpcr(__old_r); > + __new_r = __old_r | ((__mask & FE_ALL_EXCEPT) << _FPUSW_SHIFT); > + __msr_fpcr(__new_r); > + return ((__old_r >> _FPUSW_SHIFT) & FE_ALL_EXCEPT); > +} > + > +__fenv_static inline int > +fedisableexcept(int __mask) > +{ > + fenv_t __old_r, __new_r; > + > + __mrs_fpcr(__old_r); > + __new_r = __old_r & ~((__mask & FE_ALL_EXCEPT) << _FPUSW_SHIFT); > + __msr_fpcr(__new_r); > + return ((__old_r >> _FPUSW_SHIFT) & FE_ALL_EXCEPT); > +} > + > +__fenv_static inline int > +fegetexcept(void) > +{ > + fenv_t __r; > + > + __mrs_fpcr(__r); > + return ((__r & _ENABLE_MASK) >> _FPUSW_SHIFT); > +} > + > +#endif /* __BSD_VISIBLE */ > + > +#if defined(__CYGWIN__) > + > +/* Returns the currently selected precision, represented by one of the > + values of the defined precision macros. */ > +__fenv_static inline int > +fegetprec (void) > +{ > + return 0; > +} > + > +/* http://www.open-std.org/jtc1/sc22//WG14/www/docs/n752.htm: > + > + The fesetprec function establishes the precision represented by its > + argument prec. If the argument does not match a precision macro, the > + precision is not changed. > + > + The fesetprec function returns a nonzero value if and only if the > + argument matches a precision macro (that is, if and only if the requested > + precision can be established). */ > +__fenv_static inline int > +fesetprec (int prec) > +{ > + /* Indicate success. */ > + return 1; > +} > + > +#endif /* __CYGWIN__ */ > diff --git a/newlib/libc/machine/aarch64/sys/fenv.h > b/newlib/libc/machine/aarch64/sys/fenv.h > index 6b0879269..1cfbeaaf4 100644 > --- a/newlib/libc/machine/aarch64/sys/fenv.h > +++ b/newlib/libc/machine/aarch64/sys/fenv.h > @@ -77,44 +77,4 @@ extern const fenv_t *_fe_dfl_env; > #define __mrs_fpsr(__r) __asm __volatile("mrs %0, fpsr" : "=r" (__r)) > #define __msr_fpsr(__r) __asm __volatile("msr fpsr, %0" : : "r" (__r)) > > - > -#if __BSD_VISIBLE > - > -/* We currently provide no external definitions of the functions below. */ > - > -static inline int > -feenableexcept(int __mask) > -{ > - fenv_t __old_r, __new_r; > - > - __mrs_fpcr(__old_r); > - __new_r = __old_r | ((__mask & FE_ALL_EXCEPT) << _FPUSW_SHIFT); > - __msr_fpcr(__new_r); > - return ((__old_r >> _FPUSW_SHIFT) & FE_ALL_EXCEPT); > -} > - > -static inline int > -fedisableexcept(int __mask) > -{ > - fenv_t __old_r, __new_r; > - > - __mrs_fpcr(__old_r); > - __new_r = __old_r & ~((__mask & FE_ALL_EXCEPT) << _FPUSW_SHIFT); > - __msr_fpcr(__new_r); > - return ((__old_r >> _FPUSW_SHIFT) & FE_ALL_EXCEPT); > -} > - > -static inline int > -fegetexcept(void) > -{ > - fenv_t __r; > - > - __mrs_fpcr(__r); > - return ((__r & _ENABLE_MASK) >> _FPUSW_SHIFT); > -} > - > -#endif /* __BSD_VISIBLE */ > - > - > - > #endif /* !_FENV_H_ */ > diff --git a/newlib/libm/machine/aarch64/fenv.c > b/newlib/libm/machine/aarch64/fenv.c > index 3ffe23441..86f8cd5aa 100644 > --- a/newlib/libm/machine/aarch64/fenv.c > +++ b/newlib/libm/machine/aarch64/fenv.c > @@ -55,3 +55,10 @@ extern inline int feupdateenv(const fenv_t *__envp); > extern inline int feenableexcept(int __mask); > extern inline int fedisableexcept(int __mask); > extern inline int fegetexcept(void); > + > +#if defined(__CYGWIN__) > + > +extern inline int fegetprec(void); > +extern inline int fesetprec(int prec); > + > +#endif /* CYGWIN */ > diff --git a/winsup/cygwin/fenv.c b/winsup/cygwin/fenv.c > index 80f7cc52c..1558f76c2 100644 > --- a/winsup/cygwin/fenv.c > +++ b/winsup/cygwin/fenv.c > @@ -3,3 +3,13 @@ > being called from mainCRTStartup in crt0.o. */ > void _feinitialise (void) > {} > + > +#if defined(__aarch64__) > + > +#include <fenv.h> > +#include <stddef.h> > + > +/* _fe_nomask_env is exported by cygwin.din but not used at all for AArch64. > */ > +const fenv_t *_fe_nomask_env = NULL; > + > +#endif /* __aarch64__ */ > -- > 2.49.0.vfs.0.3 >
