From e65a5a562e69607756e12e8796b3705afebff074 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kamil=20=C5=9Aliwak?= <kamil.sliwak@codepoets.it>
Date: Thu, 23 Apr 2020 21:16:41 +0200
Subject: [PATCH] IRGenerationContext::internalDispatch(): Fix code generated
 when the function called via pointer does not return anything

---
 .../codegen/ir/IRGenerationContext.cpp        |  3 ++-
 ...function_returning_nothing_via_pointer.sol | 19 +++++++++++++++++++
 2 files changed, 21 insertions(+), 1 deletion(-)
 create mode 100644 test/libsolidity/semanticTests/functionCall/call_function_returning_nothing_via_pointer.sol

diff --git a/libsolidity/codegen/ir/IRGenerationContext.cpp b/libsolidity/codegen/ir/IRGenerationContext.cpp
index c3b896ee1..0410d8835 100644
--- a/libsolidity/codegen/ir/IRGenerationContext.cpp
+++ b/libsolidity/codegen/ir/IRGenerationContext.cpp
@@ -122,7 +122,7 @@ string IRGenerationContext::internalDispatch(size_t _in, size_t _out)
 				<#cases>
 				case <funID>
 				{
-					<out> := <name>(<in>)
+					<out> <assignment_op> <name>(<in>)
 				}
 				</cases>
 				default { invalid() }
@@ -133,6 +133,7 @@ string IRGenerationContext::internalDispatch(size_t _in, size_t _out)
 		YulUtilFunctions utils(m_evmVersion, m_revertStrings, m_functions);
 		templ("in", suffixedVariableNameList("in_", 0, _in));
 		templ("arrow", _out > 0 ? "->" : "");
+		templ("assignment_op", _out > 0 ? ":=" : "");
 		templ("out", suffixedVariableNameList("out_", 0, _out));
 		vector<map<string, string>> functions;
 		for (auto const& contract: mostDerivedContract().annotation().linearizedBaseContracts)
diff --git a/test/libsolidity/semanticTests/functionCall/call_function_returning_nothing_via_pointer.sol b/test/libsolidity/semanticTests/functionCall/call_function_returning_nothing_via_pointer.sol
new file mode 100644
index 000000000..569d185bd
--- /dev/null
+++ b/test/libsolidity/semanticTests/functionCall/call_function_returning_nothing_via_pointer.sol
@@ -0,0 +1,19 @@
+contract test {
+    bool public flag = false;
+
+    function f0() public {
+        flag = true;
+    }
+
+    function f() public returns (bool) {
+        function() internal x = f0;
+        x();
+        return flag;
+    }
+}
+
+// ====
+// compileViaYul: also
+// ----
+// f() -> true
+// flag() -> true