From 9cd614dd5481a4fdf552effac4820f51a10092c7 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Mika=20V=C3=A4in=C3=B6l=C3=A4?= <33728696+mvainola@users.noreply.github.com> Date: Wed, 7 Apr 2021 13:12:17 +0300 Subject: [PATCH] Workaround for GCC 11 uninit variable warnings (#946) Building Amber with GCC 11.0.1 produces some uninitialized variable warnings. This commit works around them by replacing reinterpret_cast with memcpy when type punning unsigned integers to floats. Upstream-Status: Backport [https://github.com/google/amber/commit/aa69a0ac23ea7f68dd32bbef210546a5d84c1734] --- src/float16_helper.cc | 22 ++++++++++++++++------ 1 file changed, 16 insertions(+), 6 deletions(-) diff --git a/src/float16_helper.cc b/src/float16_helper.cc index 617bd72..5cb35e7 100644 --- a/src/float16_helper.cc +++ b/src/float16_helper.cc @@ -15,6 +15,7 @@ #include "src/float16_helper.h" #include +#include // Float10 // | 9 8 7 6 5 | 4 3 2 1 0 | @@ -75,8 +76,11 @@ float HexFloat16ToFloat(const uint8_t* value) { } uint32_t hex = sign | exponent | mantissa; - float* hex_float = reinterpret_cast(&hex); - return *hex_float; + float hex_float; + static_assert((sizeof(uint32_t) == sizeof(float)), + "sizeof(uint32_t) != sizeof(float)"); + memcpy(&hex_float, &hex, sizeof(float)); + return hex_float; } // Convert float |value| whose size is 11 bits to 32 bits float @@ -89,8 +93,11 @@ float HexFloat11ToFloat(const uint8_t* value) { uint32_t mantissa = (static_cast(value[0]) & 0x3f) << 17U; uint32_t hex = exponent | mantissa; - float* hex_float = reinterpret_cast(&hex); - return *hex_float; + float hex_float; + static_assert((sizeof(uint32_t) == sizeof(float)), + "sizeof(uint32_t) != sizeof(float)"); + memcpy(&hex_float, &hex, sizeof(float)); + return hex_float; } // Convert float |value| whose size is 10 bits to 32 bits float @@ -103,8 +110,11 @@ float HexFloat10ToFloat(const uint8_t* value) { uint32_t mantissa = (static_cast(value[0]) & 0x1f) << 18U; uint32_t hex = exponent | mantissa; - float* hex_float = reinterpret_cast(&hex); - return *hex_float; + float hex_float; + static_assert((sizeof(uint32_t) == sizeof(float)), + "sizeof(uint32_t) != sizeof(float)"); + memcpy(&hex_float, &hex, sizeof(float)); + return hex_float; } } // namespace -- 2.31.1