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[[!tag open_issue_glibc]]

    $ echo 'int main() {}' | gcc -o /dev/null -static -x c -
    /usr/lib/gcc/i486-gnu/4.4.5/../../../libcrt.a(malloc.o): In function `_int_free':
    (.text+0xdc3): warning: warning: madvise is not implemented and will always fail

This is correct, but it does confuse GNU Autoconf, for example, which then
thinks that static linking is not supported and sets a flag accordingly, which
luckly no / not many packages use.

*This call does not influence the semantics of the application (except in the
case of MADV_DONTNEED), but may influence its performance.  The kernel is free
to ignore the advice.* (`man madvise`), so we may simply want to turn it into a
no-op in glibc, avoiding the link-time warning.