7 files changed, 70 insertions, 2 deletions
diff --git a/libsolidity/Compiler.cpp b/libsolidity/Compiler.cpp
index 1ef63bbf..6fb09def 100644
--- a/libsolidity/Compiler.cpp
+++ b/libsolidity/Compiler.cpp
@@ -68,6 +68,12 @@ void Compiler::compileContract(
 	packIntoContractCreator(_contract, m_runtimeContext);
 	if (m_optimize)
 		m_context.optimise(m_optimizeRuns);
+
+	if (_contract.isLibrary())
+	{
+		solAssert(m_runtimeSub != size_t(-1), "");
+		m_context.injectVersionStampIntoSub(m_runtimeSub);
+	}
 }
 
 void Compiler::compileClone(
diff --git a/libsolidity/CompilerContext.cpp b/libsolidity/CompilerContext.cpp
index 717627a5..fa7f9c77 100644
--- a/libsolidity/CompilerContext.cpp
+++ b/libsolidity/CompilerContext.cpp
@@ -20,10 +20,12 @@
  * Utilities for the solidity compiler.
  */
 
+#include <libsolidity/CompilerContext.h>
 #include <utility>
 #include <numeric>
 #include <libsolidity/AST.h>
 #include <libsolidity/Compiler.h>
+#include <libsolidity/Version.h>
 
 using namespace std;
 
@@ -177,6 +179,13 @@ void CompilerContext::resetVisitedNodes(ASTNode const* _node)
 	updateSourceLocation();
 }
 
+void CompilerContext::injectVersionStampIntoSub(size_t _subIndex)
+{
+	eth::Assembly& sub = m_asm.sub(_subIndex);
+	sub.injectStart(eth::Instruction::POP);
+	sub.injectStart(fromBigEndian<u256>(binaryVersion()));
+}
+
 eth::AssemblyItem CompilerContext::virtualFunctionEntryLabel(
 	FunctionDefinition const& _function,
 	vector<ContractDefinition const*>::const_iterator _searchStart
diff --git a/libsolidity/CompilerContext.h b/libsolidity/CompilerContext.h
index 46ebfcf8..18865091 100644
--- a/libsolidity/CompilerContext.h
+++ b/libsolidity/CompilerContext.h
@@ -128,6 +128,9 @@ public:
 	CompilerContext& operator<<(u256 const& _value) { m_asm.append(_value); return *this; }
 	CompilerContext& operator<<(bytes const& _data) { m_asm.append(_data); return *this; }
 
+	/// Prepends "PUSH <compiler version number> POP"
+	void injectVersionStampIntoSub(size_t _subIndex);
+
 	void optimise(unsigned _runs = 200) { m_asm.optimise(true, true, _runs); }
 
 	eth::Assembly const& assembly() const { return m_asm; }
diff --git a/libsolidity/Utils.h b/libsolidity/Utils.h
index 05c5fa6f..6c8e3b33 100644
--- a/libsolidity/Utils.h
+++ b/libsolidity/Utils.h
@@ -23,6 +23,7 @@
 #pragma once
 
 #include <libdevcore/Assertions.h>
+#include <libsolidity/Exceptions.h>
 
 /// Assertion that throws an InternalCompilerError containing the given description if it is not met.
 #define solAssert(CONDITION, DESCRIPTION) \
diff --git a/libsolidity/Version.cpp b/libsolidity/Version.cpp
index c6b5c509..09a6d84b 100644
--- a/libsolidity/Version.cpp
+++ b/libsolidity/Version.cpp
@@ -22,16 +22,19 @@
 
 #include <libsolidity/Version.h>
 #include <string>
+#include <libdevcore/CommonData.h>
+#include <libdevcore/Common.h>
 #include <libevmasm/Version.h>
+#include <libsolidity/Utils.h>
 #include <solidity/BuildInfo.h>
-#include <libdevcore/Common.h>
 
 using namespace dev;
 using namespace dev::solidity;
 using namespace std;
 
 char const* dev::solidity::VersionNumber = ETH_PROJECT_VERSION;
-extern string const dev::solidity::VersionString =
+
+string const dev::solidity::VersionString =
 	string(dev::solidity::VersionNumber) +
 	"-" +
 	string(DEV_QUOTED(ETH_COMMIT_HASH)).substr(0, 8) +
@@ -39,3 +42,32 @@ extern string const dev::solidity::VersionString =
 	"/" DEV_QUOTED(ETH_BUILD_TYPE) "-" DEV_QUOTED(ETH_BUILD_PLATFORM)
 	" linked to libethereum-" + eth::VersionStringLibEvmAsm;
 
+
+bytes dev::solidity::binaryVersion()
+{
+	bytes ret{0};
+	size_t i = 0;
+	auto parseDecimal = [&]()
+	{
+		size_t ret = 0;
+		solAssert('0' <= VersionString[i] && VersionString[i] <= '9', "");
+		for (; i < VersionString.size() && '0' <= VersionString[i] && VersionString[i] <= '9'; ++i)
+			ret = ret * 10 + (VersionString[i] - '0');
+		return ret;
+	};
+	ret.push_back(byte(parseDecimal()));
+	solAssert(i < VersionString.size() && VersionString[i] == '.', "");
+	++i;
+	ret.push_back(byte(parseDecimal()));
+	solAssert(i < VersionString.size() && VersionString[i] == '.', "");
+	++i;
+	ret.push_back(byte(parseDecimal()));
+	solAssert(i < VersionString.size() && VersionString[i] == '-', "");
+	++i;
+	solAssert(i + 7 < VersionString.size(), "");
+	ret += fromHex(VersionString.substr(i, 8));
+	solAssert(ret.size() == 1 + 3 + 4, "");
+
+	return ret;
+}
+
diff --git a/libsolidity/Version.h b/libsolidity/Version.h
index 6e00f07b..fea73997 100644
--- a/libsolidity/Version.h
+++ b/libsolidity/Version.h
@@ -23,6 +23,7 @@
 #pragma once
 
 #include <string>
+#include <libdevcore/Common.h>
 
 namespace dev
 {
@@ -32,5 +33,10 @@ namespace solidity
 extern char const* VersionNumber;
 extern std::string const VersionString;
 
+/// @returns a binary form of the version string, where A.B.C-HASH is encoded such that
+/// the first byte is zero, the following three bytes encode A B and C (interpreted as decimals)
+/// and HASH is interpreted as 8 hex digits and encoded into the last four bytes.
+bytes binaryVersion();
+
 }
 }
diff --git a/test/libsolidity/SolidityEndToEndTest.cpp b/test/libsolidity/SolidityEndToEndTest.cpp
index b46b405d..3cfe4975 100644
--- a/test/libsolidity/SolidityEndToEndTest.cpp
+++ b/test/libsolidity/SolidityEndToEndTest.cpp
@@ -5539,6 +5539,17 @@ BOOST_AUTO_TEST_CASE(calldata_offset)
 	BOOST_CHECK(callContractFunction("last()", encodeArgs()) == encodeDyn(string("nd")));
 }
 
+BOOST_AUTO_TEST_CASE(version_stamp_for_libraries)
+{
+	char const* sourceCode = "library lib {}";
+	m_optimize = true;
+	bytes runtimeCode = compileAndRun(sourceCode, 0, "lib");
+	BOOST_CHECK(runtimeCode.size() >= 8);
+	BOOST_CHECK_EQUAL(runtimeCode[0], int(eth::Instruction::PUSH6)); // might change once we switch to 1.x.x
+	BOOST_CHECK_EQUAL(runtimeCode[1], 1); // might change once we switch away from x.1.x
+	BOOST_CHECK_EQUAL(runtimeCode[7], int(eth::Instruction::POP));
+}
+
 BOOST_AUTO_TEST_SUITE_END()
 
 }