configure: slightly more robust looking check for math functions.

[ffmpeg] / configure

diff --git a/configure b/configure
index cc00b5b34f1bed7e23a376bb06792efab36d90f7..300852d83b2a41b3ad1800be984048d70ac9a157 100755 (executable)
--- a/configure
+++ b/configure
@@ -708,7 +708,7 @@ check_mathfunc(){
     check_ld "$@" <<EOF && enable $func
 #include <math.h>
 float foo(float f) { return $func(f); }
-int main(void){ return 0; }
+int main(void){ return (int) foo; }
 EOF
 }
 
@@ -2853,7 +2853,7 @@ check_func_headers windows.h MapViewOfFile
 check_func_headers windows.h VirtualAlloc
 
 check_header dlfcn.h
-check_header dxva2api.h
+check_header dxva2api.h -D_WIN32_WINNT=0x0600
 check_header libcrystalhd/libcrystalhd_if.h
 check_header malloc.h
 check_header poll.h