From f372ba6feaf679012417697a32d79e17b282f9c3 Mon Sep 17 00:00:00 2001
From: chriseth <chris@ethereum.org>
Date: Mon, 6 Jul 2020 16:52:51 +0200
Subject: [PATCH] Constructors cannot have calldata parameters.

---
 Changelog.md                                          |  1 +
 libsolidity/ast/AST.cpp                               | 11 ++++++++++-
 libsolidity/ast/AST.h                                 |  1 +
 .../constructor/calldata_constructor_args.sol         |  5 +++++
 4 files changed, 17 insertions(+), 1 deletion(-)
 create mode 100644 test/libsolidity/syntaxTests/constructor/calldata_constructor_args.sol

diff --git a/Changelog.md b/Changelog.md
index 837c0f1b9..fa4e46800 100644
--- a/Changelog.md
+++ b/Changelog.md
@@ -19,6 +19,7 @@ Bugfixes:
  * NatSpec: Do not consider ``////`` and ``/***`` as NatSpec comments.
  * Type Checker: Fix internal error related to ``using for`` applied to non-libraries.
  * Type Checker: Do not disallow assigning to calldata variables.
+ * Type Checker: Disallow constructor parameters with ``calldata`` data location.
  * Wasm backend: Fix code generation for for-loops with pre statements.
  * Yul: Fix source location of variable multi-assignment.
 
diff --git a/libsolidity/ast/AST.cpp b/libsolidity/ast/AST.cpp
index f3f79f451..cba5bccc3 100644
--- a/libsolidity/ast/AST.cpp
+++ b/libsolidity/ast/AST.cpp
@@ -588,6 +588,15 @@ bool VariableDeclaration::isInternalCallableParameter() const
 	return false;
 }
 
+bool VariableDeclaration::isConstructorParameter() const
+{
+	if (!isCallableOrCatchParameter())
+		return false;
+	if (auto const* function = dynamic_cast<FunctionDefinition const*>(scope()))
+		return function->isConstructor();
+	return false;
+}
+
 bool VariableDeclaration::isLibraryFunctionParameter() const
 {
 	if (!isCallableOrCatchParameter())
@@ -622,7 +631,7 @@ set<VariableDeclaration::Location> VariableDeclaration::allowedDataLocations() c
 		set<Location> locations{ Location::Memory };
 		if (isInternalCallableParameter() || isLibraryFunctionParameter() || isTryCatchParameter())
 			locations.insert(Location::Storage);
-		if (!isTryCatchParameter())
+		if (!isTryCatchParameter() && !isConstructorParameter())
 			locations.insert(Location::CallData);
 
 		return locations;
diff --git a/libsolidity/ast/AST.h b/libsolidity/ast/AST.h
index 88c3e1beb..34fefeb0a 100644
--- a/libsolidity/ast/AST.h
+++ b/libsolidity/ast/AST.h
@@ -928,6 +928,7 @@ public:
 	/// @returns true if this variable is a parameter or return parameter of an internal function
 	/// or a function type of internal visibility.
 	bool isInternalCallableParameter() const;
+	bool isConstructorParameter() const;
 	/// @returns true iff this variable is a parameter(or return parameter of a library function
 	bool isLibraryFunctionParameter() const;
 	/// @returns true if the type of the variable does not need to be specified, i.e. it is declared
diff --git a/test/libsolidity/syntaxTests/constructor/calldata_constructor_args.sol b/test/libsolidity/syntaxTests/constructor/calldata_constructor_args.sol
new file mode 100644
index 000000000..c4ce52102
--- /dev/null
+++ b/test/libsolidity/syntaxTests/constructor/calldata_constructor_args.sol
@@ -0,0 +1,5 @@
+contract C {
+    constructor(uint[] calldata) public {}
+}
+// ----
+// TypeError 6651: (29-44): Data location must be "memory" for parameter in function, but "calldata" was given.