The GNU Fortran manual documents that the c_float128 kind corresponds
to __float128, but in fact the implementation uses float128_type_node,
which is _Float128. Both refer to the 128-bit IEEE/ISO encoding, but
some targets including aarch64 only define _Float128 and not __float128,
and do not provide quadmath.h. This caused errors in some test cases
referring to __float128.
This patch changes the documentation (including code comments) and
test cases to use _Float128 to match the implementation.
2021-09-16 Sandra Loosemore <sandra@codesourcery.com>
gcc/fortran/
* intrinsic.texi (ISO_C_BINDING): Change C_FLOAT128 to correspond
to _Float128 rather than __float128.
* iso-c-binding.def (c_float128): Update comments.
* trans-intrinsic.c (gfc_builtin_decl_for_float_kind): Likewise.
(build_round_expr): Likewise.
(gfc_build_intrinsic_lib_fndcecls): Likewise.
* trans-types.h (gfc_real16_is_float128): Likewise.
gcc/testsuite/
* gfortran.dg/PR100914.c: Do not include quadmath.h. Use
_Float128 _Complex instead of __complex128.
* gfortran.dg/PR100914.f90: Add -Wno-pedantic to suppress error
about use of _Float128.
* gfortran.dg/c-interop/typecodes-array-float128-c.c: Use
_Float128 instead of __float128.
* gfortran.dg/c-interop/typecodes-sanity-c.c: Likewise.
* gfortran.dg/c-interop/typecodes-scalar-float128-c.c: Likewise.
* lib/target-supports.exp
(check_effective_target_fortran_real_c_float128): Update comments.
libgfortran/
* ISO_Fortran_binding.h: Update comments.
* runtime/ISO_Fortran_binding.c: Likewise.