Minor fixes.

* Update libpotassco.
* Ensure that memcpy/memmove is not called with a null src/dest.
* Fix incorrect use of setEnumerationConstraint() in "testMtBug1".
* Fix potential uninitialized read in DefaultMinimize::attach.

CMakeLists.txt

@@ -1,5 +1,5 @@
 cmake_minimum_required(VERSION 3.1)
-project(CLASP VERSION 3.3.10.14 LANGUAGES CXX)
+project(CLASP VERSION 3.3.10.15 LANGUAGES CXX)
 # Enable folders in IDEs like Visual Studio
 set_property(GLOBAL PROPERTY USE_FOLDERS ON)
 if (POLICY CMP0063)

clasp/util/left_right_sequence.h

@@ -1,5 +1,5 @@
 //
-// Copyright (c) 2010-2017 Benjamin Kaufmann
+// Copyright (c) 2010-present Benjamin Kaufmann
 //
 // This file is part of Clasp. See http://www.cs.uni-potsdam.de/clasp/
 //
@@ -179,11 +179,13 @@ void left_right_rep<L, R>::realloc() {
 	size_type min_cap = 4 * block_size;
 	if (new_cap < min_cap) new_cap = min_cap;
 	buf_type* temp = (buf_type*)::operator new(new_cap*sizeof(buf_type));
-	// copy left
-	std::memcpy(temp, begin(), left_size()*sizeof(L));
-	// copy right
 	size_type r = cap_ - right_;
-	std::memcpy(temp+(new_cap-r), right(), right_size() * sizeof(R));
+	if (!empty()) {
+		// copy left
+		std::memcpy(temp, begin(), left_size()*sizeof(L));
+		// copy right
+		std::memcpy(temp+(new_cap-r), right(), right_size() * sizeof(R));
+	}
 	// swap
 	release();
 	buf_   = temp;
@@ -282,8 +284,10 @@ class left_right_sequence : public bk_lib::detail::select_base<L, R, i>::type {
 			buf_type* e = this->extra();
 			size_type c = base_type::inline_raw_cap;
 			size_type r = c - (this->right_size()*sizeof(right_type));
-			std::memcpy(e,   this->begin(), this->left_size() * sizeof(left_type));
-			std::memcpy(e+r, this->right(), this->right_size()* sizeof(right_type));
+			if (!this->empty()) {
+				std::memcpy(e,   this->begin(), this->left_size() * sizeof(left_type));
+				std::memcpy(e+r, this->right(), this->right_size()* sizeof(right_type));
+			}
 			this->release();
 			this->buf_  = e;
 			this->cap_  = c;
@@ -330,8 +334,10 @@ void left_right_sequence<L, R, i>::copy(const left_right_sequence& other) {
 	}
 	this->left_ = other.left_;
 	this->right_= this->cap_ - (other.right_size()*sizeof(right_type));
-	std::memcpy(this->begin(), other.begin(), other.left_size()*sizeof(left_type));
-	std::memcpy(this->right(), const_cast<left_right_sequence&>(other).right(), other.right_size()*sizeof(right_type));
+	if (!other.empty()) {
+		std::memcpy(this->begin(), other.begin(), other.left_size()*sizeof(left_type));
+		std::memcpy(this->right(), const_cast<left_right_sequence&>(other).right(), other.right_size()*sizeof(right_type));
+	}
 }
 
 template <class L, class R, unsigned i>

clasp/util/pod_vector.h

@@ -93,7 +93,9 @@ namespace bk_lib { namespace detail {
 	struct Memcpy {
 		Memcpy(const T* first) : first_(first) {}
 		void operator()(T* out, std::size_t n) const {
-			std::memcpy(out, first_, n*sizeof(T));
+			if (out && n) {
+				std::memcpy(out, first_, n*sizeof(T));
+			}
 		}
 		const T* first_;
 	};
@@ -181,7 +183,9 @@ class pod_vector {
 	 * \post size() == other.size() && capacity() == other.size()
 	 */
 	pod_vector(const pod_vector& other) : ebo_(other.size(), other.get_allocator()) {
-		std::memcpy(ebo_.buf, other.begin(), other.size()*sizeof(T));
+		if (const_pointer buf = other.begin()) {
+			std::memcpy(ebo_.buf, buf, other.size()*sizeof(T));
+		}
 		ebo_.size = other.size();
 	}
 
@@ -341,7 +345,7 @@ class pod_vector {
 
 	//! reallocates storage if necessary but never changes the size() of this pod_vector.
 	/*!
-	 * \note if n is <= capacity() reserve is a noop. Otherwise a reallocation takes place
+	 * \note if n is <= capacity() reserve is a noop. Otherwise, a reallocation takes place
 	 * and capacity() >= n after reserve returned.
 	 * \note reallocation invalidates all references, pointers and iterators referring to
 	 * elements in this pod_vector.
@@ -351,7 +355,9 @@ class pod_vector {
 	void reserve(size_type n) {
 		if (n > capacity()) {
 			T* temp = ebo_.allocate(n);
-			std::memcpy(temp, ebo_.buf, size()*sizeof(T));
+			if (ebo_.buf) {
+				std::memcpy(temp, ebo_.buf, size()*sizeof(T));
+			}
 			ebo_.release();
 			ebo_.buf = temp;
 			ebo_.cap = n;
@@ -451,7 +457,9 @@ class pod_vector {
 	void append_realloc(size_type n, const T& x) {
 		size_type new_cap = grow_size(n);
 		pointer temp      = ebo_.allocate(new_cap);
-		std::memcpy(temp, ebo_.buf, size()*sizeof(T));
+		if (ebo_.buf) {
+			std::memcpy(temp, ebo_.buf, size()*sizeof(T));
+		}
 		detail::fill(temp+size(), temp+size()+n, x);
 		ebo_.release();
 		ebo_.buf  = temp;
@@ -460,7 +468,9 @@ class pod_vector {
 	}
 	void move_right(iterator pos, size_type n) {
 		assert( (pos || n == 0) && (ebo_.eos() - pos) >= (int)n);
-		std::memmove(pos + n, pos, (end() - pos) * sizeof(T));
+		if (pos) {
+			std::memmove(pos + n, pos, (end() - pos) * sizeof(T));
+		}
 	}
 	template <class It>
 	void insert_range(iterator pos, It first, It last,  std::random_access_iterator_tag,
@@ -499,11 +509,15 @@ class pod_vector {
 			pointer temp      = ebo_.allocate(new_cap);
 			size_type prefix  = static_cast<size_type>(pos-begin());
 			// copy prefix
-			std::memcpy(temp, begin(), prefix*sizeof(T));
+			if (const_pointer buf = begin()) {
+				std::memcpy(temp, buf, prefix*sizeof(T));
+			}
 			// insert new stuff
 			pred(temp+prefix, n);
 			// copy suffix
-			std::memcpy(temp+prefix+n, pos, (end()-pos)*sizeof(T));
+			if (pos) {
+				std::memcpy(temp+prefix+n, pos, (end()-pos)*sizeof(T));
+			}
 			ebo_.release();
 			ebo_.buf  = temp;
 			ebo_.size+= n;

src/clause.cpp

@@ -65,7 +65,9 @@ SharedLiterals* SharedLiterals::newShareable(const Literal* lits, uint32 size, C
 SharedLiterals::SharedLiterals(const Literal* a_lits, uint32 size, ConstraintType t, uint32 refs)
 	: size_type_( (size << 2) + t ) {
 	refCount_ = std::max(uint32(1),refs);
-	std::memcpy(lits_, a_lits, size*sizeof(Literal));
+	if (a_lits) {
+		std::memcpy(lits_, a_lits, size*sizeof(Literal));
+	}
 }
 
 uint32 SharedLiterals::simplify(Solver& s) {

src/minimize_constraint.cpp

@@ -1,5 +1,5 @@
 //
-// Copyright (c) 2010-2017 Benjamin Kaufmann
+// Copyright (c) 2010-present Benjamin Kaufmann
 //
 // This file is part of Clasp. See http://www.cs.uni-potsdam.de/clasp/
 //
@@ -193,7 +193,10 @@ DefaultMinimize::DefaultMinimize(SharedData* d, const OptParams& params)
 	, pos_(d->lits)
 	, undo_(0)
 	, undoTop_(0)
-	, size_(d->numRules()) {
+	, posTop_(0)
+	, size_(d->numRules())
+	, actLev_(0)
+	, step_() {
 	step_.type = params.algo;
 	if (step_.type == OptParams::bb_hier && d->numRules() == 1) {
 		step_.type = 0;

tests/minimize_test.cpp

@@ -1,5 +1,5 @@
 //
-// Copyright (c) 2006-2017 Benjamin Kaufmann
+// Copyright (c) 2006-present Benjamin Kaufmann
 //
 // This file is part of Clasp. See http://www.cs.uni-potsdam.de/clasp/
 //
@@ -1100,8 +1100,8 @@ TEST_CASE("Core-guided minimize", "[constraint][asp]") {
 		p.opts |= OptParams::usc_disjoint;
 		MinimizeConstraint* m1 = data->attach(s1, p);
 		MinimizeConstraint* m2 = data->attach(s2, p);
-		s1.setEnumerationConstraint(m1);
-		s2.setEnumerationConstraint(m2);
+		SingleOwnerPtr<Constraint, DestroyObject> del1(m1);
+		SingleOwnerPtr<Constraint, DestroyObject> del2(m2);
 		BasicSolve solve(s1);
 		LitVec gp;
 		while (m1->integrate(s1) || m1->handleUnsat(s1, true, gp)) {