From d15b96b498d7cad51a0cb1dd949f70a04af246e9 Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Sun, 31 Oct 2021 19:11:04 +0200
Subject: [PATCH] Check for self-assignment in non-trivial assignment operators

---
 source/core/refptr.h      | 6 ++++++
 source/core/variant.h     | 3 +++
 source/fs/stat.cpp        | 3 +++
 source/strings/format.cpp | 3 +++
 4 files changed, 15 insertions(+)

diff --git a/source/core/refptr.h b/source/core/refptr.h
index 34560ec..79401dc 100644
--- a/source/core/refptr.h
+++ b/source/core/refptr.h
@@ -151,6 +151,9 @@ template<typename T>
 template<typename U>
 RefPtr<T> &RefPtr<T>::assign(const RefPtr<U> &p)
 {
+	if(static_cast<const void *>(&p)==this)
+		return *this;
+
 	decref();
 	data = p.data;
 	counts = p.counts;
@@ -195,6 +198,9 @@ template<typename T>
 template<typename U>
 WeakPtr<T> &WeakPtr<T>::assign(const WeakPtr<U> &p)
 {
+	if(&p==this)
+		return *this;
+
 	decref();
 	data = p.get();
 	counts = (data ? p.counts : nullptr);
diff --git a/source/core/variant.h b/source/core/variant.h
index 443befb..338ec90 100644
--- a/source/core/variant.h
+++ b/source/core/variant.h
@@ -69,6 +69,9 @@ public:
 
 	Variant &operator=(const Variant &v)
 	{
+		if(&v==this)
+			return *this;
+
 		delete store;
 		store = (v.store ? v.store->clone() : nullptr);
 		return *this;
diff --git a/source/fs/stat.cpp b/source/fs/stat.cpp
index 773cdef..e296ead 100644
--- a/source/fs/stat.cpp
+++ b/source/fs/stat.cpp
@@ -19,6 +19,9 @@ Stat::Stat(const Stat &other):
 
 Stat &Stat::operator=(const Stat &other)
 {
+	if(&other==this)
+		return *this;
+
 	exists = other.exists;
 	type = other.type;
 	size = other.size;
diff --git a/source/strings/format.cpp b/source/strings/format.cpp
index d2065e9..42926e1 100644
--- a/source/strings/format.cpp
+++ b/source/strings/format.cpp
@@ -19,6 +19,9 @@ Formatter::Formatter(const Formatter &other):
 
 Formatter &Formatter::operator=(const Formatter &other)
 {
+	if(&other==this)
+		return *this;
+
 	fmt = other.fmt;
 	pos = fmt.begin()+(other.pos-other.fmt.begin());
 	result = other.result;
-- 
2.43.0