From b8b0c39c77bf547506b67041dda6646f92308799 Mon Sep 17 00:00:00 2001
From: Fabian Homborg <FHomborg@gmail.com>
Date: Sat, 5 Jan 2019 12:31:24 +0100
Subject: [PATCH] fish_tests: Use std::isnan

Fixes the tests on Ubuntu 16.04 "xenial".
---
 src/fish_tests.cpp | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/fish_tests.cpp b/src/fish_tests.cpp
index abe21a2e5..e5a3d9426 100644
--- a/src/fish_tests.cpp
+++ b/src/fish_tests.cpp
@@ -29,6 +29,7 @@
 #include <algorithm>
 #include <array>
 #include <atomic>
+#include <cmath>
 #include <functional>
 #include <memory>
 #include <set>
@@ -2302,7 +2303,7 @@ static void test_wcstod() {
         wchar_t *wide_end = nullptr;
         double val1 = wcstod(a, &wide_end);
         double val2 = strtod(b, &narrow_end);
-        do_test((isnan(val1) && isnan(val2)) || fabs(val1 - val2) <= __DBL_EPSILON__);
+        do_test((std::isnan(val1) && std::isnan(val2)) || fabs(val1 - val2) <= __DBL_EPSILON__);
         do_test(wide_end - a == narrow_end - b);
     };
     tod_test(L"", "");