The existing test whether "-lm" needs to be included or not is insufficient as it reports false negative on Fedora20/ppc64. As the result, qemu-nbd/qemu-io/qemu-img tools cannot compile.
This replaces sin() with log() in the test. Signed-off-by: Alexey Kardashevskiy <a...@ozlabs.ru> --- The bug was triggered by efc6de0d0eb21bbd8fbc90da1faf7dd8ed9f5321 "block/iscsi: handle BUSY condition" which does not anything wrong :) It compiled well on Fedora19 though what is weird. Is log() good enough or we need to test for both? Thanks. ps. this is my test on the system upgraded from fc19 yesterday: [aik@vpl2 ~]$ cat b.c #include <math.h> int main(void) { return isnan(log(0.0)); } [aik@vpl2 ~]$ gcc b.c -o b /tmp/ccqp1EI4.o: In function `main': b.c:(.text+0x20): undefined reference to `log' collect2: error: ld returned 1 exit status [aik@vpl2 ~]$ gcc b.c -o b -lm [aik@vpl2 ~]$ cat /etc/issue Fedora release 20 (Heisenbug) Kernel \r on an \m (\l) --- configure | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/configure b/configure index 23ecb37..c7a2922 100755 --- a/configure +++ b/configure @@ -3453,7 +3453,7 @@ fi # Do we need libm cat > $TMPC << EOF #include <math.h> -int main(void) { return isnan(sin(0.0)); } +int main(void) { return isnan(log(0.0)); } EOF if compile_prog "" "" ; then : -- 2.0.0