diff --git a/pcsx2/DEV9/Win32/pcap_io_win32.cpp b/pcsx2/DEV9/Win32/pcap_io_win32.cpp
index da480f99ea..e8eb3232dc 100644
--- a/pcsx2/DEV9/Win32/pcap_io_win32.cpp
+++ b/pcsx2/DEV9/Win32/pcap_io_win32.cpp
@@ -91,7 +91,7 @@ bool load_pcap()
 		len = GetDllDirectory(len, oldDllDir);
 		if (len == 0)
 		{
-			delete oldDllDir;
+			delete[] oldDllDir;
 			return false;
 		}
 	}
@@ -104,7 +104,7 @@ bool load_pcap()
 
 	//Reset DllDirectory
 	SetDllDirectory(oldDllDir);
-	delete oldDllDir;
+	delete[] oldDllDir;
 
 	//Did we succeed?
 	if (hpcap == nullptr)
diff --git a/pcsx2/DebugTools/BiosDebugData.cpp b/pcsx2/DebugTools/BiosDebugData.cpp
index 75a536147b..b1cf87a713 100644
--- a/pcsx2/DebugTools/BiosDebugData.cpp
+++ b/pcsx2/DebugTools/BiosDebugData.cpp
@@ -29,7 +29,7 @@ std::vector<EEThread> getEEThreads()
 	{
 		EEThread thread;
 
-		EEInternalThread* internal = (EEInternalThread*) PSM(start+tid*sizeof(EEInternalThread));
+		EEInternalThread* internal = static_cast<EEInternalThread*>(PSM(start + tid * sizeof(EEInternalThread)));
 		if (internal->status != THS_BAD)
 		{
 			thread.tid = tid;
diff --git a/pcsx2/DebugTools/DisassemblyManager.cpp b/pcsx2/DebugTools/DisassemblyManager.cpp
index d20f55a0f7..ea310b7de5 100644
--- a/pcsx2/DebugTools/DisassemblyManager.cpp
+++ b/pcsx2/DebugTools/DisassemblyManager.cpp
@@ -457,6 +457,7 @@ void DisassemblyFunction::generateBranchLines()
 		if (opInfo.isBranch && !opInfo.isBranchToRegister && !opInfo.isLinkedBranch && inFunction)
 		{
 			BranchLine line;
+			line.laneIndex = 0;
 			if (opInfo.branchTarget < funcPos)
 			{
 				line.first = opInfo.branchTarget;
@@ -471,7 +472,7 @@ void DisassemblyFunction::generateBranchLines()
 			lines.push_back(line);
 		}
 	}
-			
+
 	std::sort(lines.begin(),lines.end());
 	for (size_t i = 0; i < lines.size(); i++)
 	{
@@ -748,7 +749,7 @@ void DisassemblyMacro::setMacroLi(u32 _immediate, u8 _rt)
 	numOpcodes = 2;
 }
 
-void DisassemblyMacro::setMacroMemory(std::string _name, u32 _immediate, u8 _rt, int _dataSize)
+void DisassemblyMacro::setMacroMemory(const std::string& _name, u32 _immediate, u8 _rt, int _dataSize)
 {
 	type = MACRO_MEMORYIMM;
 	name = _name;
@@ -1021,7 +1022,7 @@ void DisassemblyData::createLines()
 }
 
 
-DisassemblyComment::DisassemblyComment(DebugInterface* _cpu, u32 _address, u32 _size, std::string _name, std::string _param)
+DisassemblyComment::DisassemblyComment(DebugInterface* _cpu, u32 _address, u32 _size, const std::string& _name, const std::string& _param)
 	: cpu(_cpu), address(_address), size(_size), name(_name), param(_param)
 {
 
diff --git a/pcsx2/DebugTools/DisassemblyManager.h b/pcsx2/DebugTools/DisassemblyManager.h
index bd5165c5ce..198ff9d2c9 100644
--- a/pcsx2/DebugTools/DisassemblyManager.h
+++ b/pcsx2/DebugTools/DisassemblyManager.h
@@ -115,7 +115,7 @@ public:
 	virtual ~DisassemblyMacro() { };
 
 	void setMacroLi(u32 _immediate, u8 _rt);
-	void setMacroMemory(std::string _name, u32 _immediate, u8 _rt, int _dataSize);
+	void setMacroMemory(const std::string& _name, u32 _immediate, u8 _rt, int _dataSize);
 
 	virtual void recheck() { };
 	virtual int getNumLines() { return 1; };
@@ -171,7 +171,7 @@ private:
 class DisassemblyComment: public DisassemblyEntry
 {
 public:
-	DisassemblyComment(DebugInterface* _cpu, u32 _address, u32 _size, std::string name, std::string param);
+	DisassemblyComment(DebugInterface* _cpu, u32 _address, u32 _size,const std::string& name, const std::string& param);
 	virtual ~DisassemblyComment() { };
 
 	virtual void recheck() { };
diff --git a/pcsx2/DebugTools/MipsAssembler.cpp b/pcsx2/DebugTools/MipsAssembler.cpp
index c83ef2a323..a10c84c877 100644
--- a/pcsx2/DebugTools/MipsAssembler.cpp
+++ b/pcsx2/DebugTools/MipsAssembler.cpp
@@ -462,8 +462,6 @@ bool CMipsInstruction::parseOpcode(const tMipsOpcode& SourceOpcode, const char*
 
 bool CMipsInstruction::LoadEncoding(const tMipsOpcode& SourceOpcode, const char* Line)
 {
-	int RetLen;
-
 	immediateType = MIPS_NOIMMEDIATE;
 	registers.reset();
 
@@ -481,6 +479,7 @@ bool CMipsInstruction::LoadEncoding(const tMipsOpcode& SourceOpcode, const char*
 
 	if (!(*SourceEncoding == 0 && *Line == 0))
 	{
+		int RetLen;
 		while (*SourceEncoding != 0)
 		{
 			while (*Line == ' ' || *Line == '\t') Line++;