[Bug libstdc++/56475] Incorrect result of configure test for /dev/random (_GLIBCXX_USE_RANDOM_TR1) for MinGW platform (and others?)

[k2k at narod dot ru]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56475

--- Comment #5 from Karlson2k <k2k at narod dot ru> 2013-02-27 22:07:21 UTC ---
(In reply to comment #3)
> Well, AC_TRY_RUN is for sure the wrong approach here.  As such tests are
> failing badly on cross-compilers.
> I think sanest way to solve this is by special-casing mingw targets.

This test is already skipped for cross-compilers and done only for native
compilers.
So AC_TRY_RUN is the only solution, that can check compiler's capabilities (and
not the shell's).