[Bug libstdc++/82644] Non-standard hypergeometric special functions defined in strict modes

["redi at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82644

--- Comment #7 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Author: redi
Date: Tue Jun 19 13:16:44 2018
New Revision: 261743

URL: https://gcc.gnu.org/viewcvs?rev=261743&root=gcc&view=rev
Log:
PR libstdc++/82644 define TR1 hypergeometric functions in strict modes

Following a recent change for PR 82644 the non-standard hypergeomtric
functions are not defined by <cmath> when __STRICT_ANSI__ is defined
(e.g. for -std=c++17, or -std=c++14 -D__STDCPP_WANT_MATH_SPEC_FUNCS__).
That caused errors in <tr1/cmath> because the using-declarations for
tr1::hyperg et al are invalid in strict modes.

The solution is to define the TR1 hypergeometric functions inline in
<tr1/cmath> if __STRICT_ANSI__ is defined.

Backport from mainline
2018-05-03  Jonathan Wakely  <jwakely@redhat.com>

        PR libstdc++/82644
        * include/tr1/cmath [__STRICT_ANSI__] (hypergf, hypergl, hyperg): Use
        inline definitions instead of using-declarations.
        [__STRICT_ANSI__] (conf_hypergf, conf_hypergl, conf_hyperg): Likewise.
        * testsuite/tr1/5_numerical_facilities/special_functions/
        07_conf_hyperg/compile_cxx17.cc: New.
        * testsuite/tr1/5_numerical_facilities/special_functions/
        17_hyperg/compile_cxx17.cc: New.

Added:
   
branches/gcc-8-branch/libstdc++-v3/testsuite/tr1/5_numerical_facilities/special_functions/07_conf_hyperg/compile_cxx17.cc
   
branches/gcc-8-branch/libstdc++-v3/testsuite/tr1/5_numerical_facilities/special_functions/17_hyperg/compile_cxx17.cc
Modified:
    branches/gcc-8-branch/libstdc++-v3/ChangeLog
    branches/gcc-8-branch/libstdc++-v3/include/tr1/cmath