From eafe0056721d828636be540cddf3c1226f88f334 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?L=C3=A9o=20Lam?= <leo@leolam.fr>
Date: Wed, 16 Dec 2020 15:01:20 +0100
Subject: [PATCH] Fix -Wclass-memaccess warnings

We want to clear/memset the padding bytes, not just each member,
so using assignment or {} initialization is not an option.

To silence the warnings, cast the object pointer to u8* (which is not
undefined behavior) to make it explicit to the compiler that we want
to fill the object representation.
---
 Source/Core/Core/HW/GCMemcard/GCMemcard.cpp      | 6 +++---
 Source/Core/VideoBackends/Software/SetupUnit.cpp | 2 +-
 Source/Core/VideoCommon/BPStructs.cpp            | 2 +-
 Source/Core/VideoCommon/ShaderCache.cpp          | 2 +-
 Source/Core/VideoCommon/VideoBackendBase.cpp     | 4 ++--
 5 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/Source/Core/Core/HW/GCMemcard/GCMemcard.cpp b/Source/Core/Core/HW/GCMemcard/GCMemcard.cpp
index c12d4e9819..6bf6e1468c 100644
--- a/Source/Core/Core/HW/GCMemcard/GCMemcard.cpp
+++ b/Source/Core/Core/HW/GCMemcard/GCMemcard.cpp
@@ -931,7 +931,7 @@ GCMemcardRemoveFileRetVal GCMemcard::RemoveFile(u8 index)  // index in the direc
   // here that has an empty file with the filename "Broken File000" where the actual deleted file
   // was. Determine when exactly this happens and if this is neccessary for anything.
 
-  memset(&(UpdatedDir.m_dir_entries[index]), 0xFF, DENTRY_SIZE);
+  memset(reinterpret_cast<u8*>(&UpdatedDir.m_dir_entries[index]), 0xFF, DENTRY_SIZE);
   UpdatedDir.m_update_counter = UpdatedDir.m_update_counter + 1;
   UpdateDirectory(UpdatedDir);
 
@@ -1623,7 +1623,7 @@ std::pair<u32, u32> Header::CalculateSerial() const
 
 DEntry::DEntry()
 {
-  memset(this, 0xFF, DENTRY_SIZE);
+  memset(reinterpret_cast<u8*>(this), 0xFF, DENTRY_SIZE);
 }
 
 std::string DEntry::GCI_FileName() const
@@ -1678,7 +1678,7 @@ GCMemcardErrorCode Header::CheckForErrors(u16 card_size_mbits) const
 
 Directory::Directory()
 {
-  memset(this, 0xFF, BLOCK_SIZE);
+  memset(reinterpret_cast<u8*>(this), 0xFF, BLOCK_SIZE);
   m_update_counter = 0;
   m_checksum = Common::swap16(0xF003);
   m_checksum_inv = 0;
diff --git a/Source/Core/VideoBackends/Software/SetupUnit.cpp b/Source/Core/VideoBackends/Software/SetupUnit.cpp
index 589d404552..3cdbbee614 100644
--- a/Source/Core/VideoBackends/Software/SetupUnit.cpp
+++ b/Source/Core/VideoBackends/Software/SetupUnit.cpp
@@ -25,7 +25,7 @@ void SetupUnit::Init(u8 primitiveType)
 
 OutputVertexData* SetupUnit::GetVertex()
 {
-  memset(m_VertWritePointer, 0, sizeof(*m_VertWritePointer));
+  memset(reinterpret_cast<u8*>(m_VertWritePointer), 0, sizeof(*m_VertWritePointer));
   return m_VertWritePointer;
 }
 
diff --git a/Source/Core/VideoCommon/BPStructs.cpp b/Source/Core/VideoCommon/BPStructs.cpp
index 585b072727..2376fd0840 100644
--- a/Source/Core/VideoCommon/BPStructs.cpp
+++ b/Source/Core/VideoCommon/BPStructs.cpp
@@ -43,7 +43,7 @@ static const float s_gammaLUT[] = {1.0f, 1.7f, 2.2f, 1.0f};
 
 void BPInit()
 {
-  memset(&bpmem, 0, sizeof(bpmem));
+  memset(reinterpret_cast<u8*>(&bpmem), 0, sizeof(bpmem));
   bpmem.bpMask = 0xFFFFFF;
 }
 
diff --git a/Source/Core/VideoCommon/ShaderCache.cpp b/Source/Core/VideoCommon/ShaderCache.cpp
index f8b4b881f0..7383dc6595 100644
--- a/Source/Core/VideoCommon/ShaderCache.cpp
+++ b/Source/Core/VideoCommon/ShaderCache.cpp
@@ -188,7 +188,7 @@ template <typename SerializedUidType, typename UidType>
 static void SerializePipelineUid(const UidType& uid, SerializedUidType& serialized_uid)
 {
   // Convert to disk format. Ensure all padding bytes are zero.
-  std::memset(&serialized_uid, 0, sizeof(serialized_uid));
+  std::memset(reinterpret_cast<u8*>(&serialized_uid), 0, sizeof(serialized_uid));
   serialized_uid.vertex_decl = uid.vertex_format->GetVertexDeclaration();
   serialized_uid.vs_uid = uid.vs_uid;
   serialized_uid.gs_uid = uid.gs_uid;
diff --git a/Source/Core/VideoCommon/VideoBackendBase.cpp b/Source/Core/VideoCommon/VideoBackendBase.cpp
index 20f4d116a6..2f7e92664a 100644
--- a/Source/Core/VideoCommon/VideoBackendBase.cpp
+++ b/Source/Core/VideoCommon/VideoBackendBase.cpp
@@ -295,8 +295,8 @@ void VideoBackendBase::DoState(PointerWrap& p)
 
 void VideoBackendBase::InitializeShared()
 {
-  memset(&g_main_cp_state, 0, sizeof(g_main_cp_state));
-  memset(&g_preprocess_cp_state, 0, sizeof(g_preprocess_cp_state));
+  memset(reinterpret_cast<u8*>(&g_main_cp_state), 0, sizeof(g_main_cp_state));
+  memset(reinterpret_cast<u8*>(&g_preprocess_cp_state), 0, sizeof(g_preprocess_cp_state));
   memset(texMem, 0, TMEM_SIZE);
 
   // do not initialize again for the config window