From b71c491f006d04613b6b61534e18144fa31b9257 Mon Sep 17 00:00:00 2001
From: Xiang Xiao <xiaoxiang@xiaomi.com>
Date: Mon, 29 Jun 2020 22:40:25 +0800
Subject: [PATCH] libc/math: Fix warning: dereferencing type-punned pointer
 will break strict-aliasing rules

Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
Change-Id: I15aa5d664c20ea7bb95ba60e056134d2ff933db9
---
 libs/libc/math/lib_libsqrtapprox.c | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/libs/libc/math/lib_libsqrtapprox.c b/libs/libc/math/lib_libsqrtapprox.c
index c0cd0af18e..69c4bfda69 100644
--- a/libs/libc/math/lib_libsqrtapprox.c
+++ b/libs/libc/math/lib_libsqrtapprox.c
@@ -38,13 +38,16 @@
 
 float lib_sqrtapprox(float x)
 {
-  int32_t i;
+  union
+  {
+    int32_t i;
+    float x;
+  } u;
 
   /* Floats + bit manipulation = +inf fun! */
 
-  i = *((int32_t *) & x);
-  i = 0x1fc00000 + (i >> 1);
-  x = *((float *)&i);
+  u.x = x;
+  u.i = 0x1fc00000 + (u.i >> 1);
 
-  return x;
+  return u.x;
 }