From cdf84806a129a33155d8f93342d377884de9b563 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Thu, 23 Feb 2012 16:20:05 +0000 Subject: [PATCH] configure: Check whether makecontext() is a glibc stub function On some systems (notably ARM Linux) glibc provides implementations of makecontext(), getcontext() and friends which are stubs which always return failure. Make the configure test for makecontext() also check for the presence of the __stub_makecontext macro which indicates the presence of these stubs, so we can avoid trying to use them and fall back to a different coroutine implementation instead. Signed-off-by: Peter Maydell Signed-off-by: Anthony Liguori --- configure | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/configure b/configure index b22fcda3cf..f9d533004b 100755 --- a/configure +++ b/configure @@ -2723,11 +2723,15 @@ fi ########################################## # check if we have makecontext +# (and that it's not a glibc stub which always returns -1) ucontext_coroutine=no if test "$darwin" != "yes"; then cat > $TMPC << EOF #include +#ifdef __stub_makecontext +#error Ignoring glibc stub makecontext which will always fail +#endif int main(void) { makecontext(0, 0, 0); return 0; } EOF if compile_prog "" "" ; then