From 2dd55590fd09ad506680b4888b4cf19f09d3eccc Mon Sep 17 00:00:00 2001
From: Prabir Pradhan <prabirmsp@google.com>
Date: Wed, 18 Aug 2021 08:49:49 -0700
Subject: [PATCH] Undefine NAN after including it in Looper.h

Looper.h needs to include the header for unordered_map, which itself
includes math.h, which defines the macro NAN. Some HALs use enums called
NAN, which causes a build error if the NAN macro is defined. We need to
undef NAN in these cases after including Looper.h.

Bug: 195020232
Test: presubmit: checkbuild
Merged-In: I63bba8ea809a12571ddc88cd1d20f2adeedf0b30
Change-Id: I63bba8ea809a12571ddc88cd1d20f2adeedf0b30
(cherry picked from commit dda604440bd546c041106624c37dda4569420b9d)
(cherry picked from commit 84a19f64f5fd2786a96b85fc5db88c1be82b6b0c)
---
 wifi/1.5/default/wifi.h | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/wifi/1.5/default/wifi.h b/wifi/1.5/default/wifi.h
index 840bdfd927..c94ef3f4cf 100644
--- a/wifi/1.5/default/wifi.h
+++ b/wifi/1.5/default/wifi.h
@@ -17,11 +17,15 @@
 #ifndef WIFI_H_
 #define WIFI_H_
 
-#include <functional>
+// HACK: NAN is a macro defined in math.h, which can be included in various
+// headers. This wifi HAL uses an enum called NAN, which does not compile when
+// the macro is defined. Undefine NAN to work around it.
+#undef NAN
+#include <android/hardware/wifi/1.5/IWifi.h>
 
 #include <android-base/macros.h>
-#include <android/hardware/wifi/1.5/IWifi.h>
 #include <utils/Looper.h>
+#include <functional>
 
 #include "hidl_callback_util.h"
 #include "wifi_chip.h"