Add support for the QNX operating system.

src/qnx-math.h

Index: src/qnx-math.h
diff --git a/test/mjsunit/lithium/MathExp.js b/src/qnx-math.h
similarity index 88%
copy from test/mjsunit/lithium/MathExp.js
copy to src/qnx-math.h
index 854ff5fd7fd2a7a22bcc3557e4e2bb4c01d9b83f..bd8474599b6ecdceec5635504891c55e52c95127 100644
--- a/test/mjsunit/lithium/MathExp.js
+++ b/src/qnx-math.h
@@ -25,15 +25,18 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-// Flags: --allow-natives-syntax
+#ifndef V8_QNX_MATH_H_
+#define V8_QNX_MATH_H_
 
-function foo(x) {
-  return Math.exp(x);
-}
+#include <cmath>
 
-foo(12.3);
-var r1 = foo(12.3);
-%OptimizeFunctionOnNextCall(foo);
-var r2 = foo(12.3);
+#undef fpclassify
+#undef isfinite
+#undef isinf
+#undef isnan
+#undef isnormal
+#undef signbit
 
-assertEquals(r1, r2);
+using std::lrint;
+
+#endif  // V8_QNX_MATH_H_