fix an inlining bug where a void function has an unreachable body

3 files changed, 27 insertions, 1 deletions

diff --git a/src/passes/Inlining.cpp b/src/passes/Inlining.cpp
index 710fc00ff..192480d26 100644
--- a/src/passes/Inlining.cpp
+++ b/src/passes/Inlining.cpp
@@ -155,7 +155,6 @@ static Expression* doInlining(Module* module, Function* into, InliningAction& ac
   auto* call = (*action.callSite)->cast<Call>();
   Builder builder(*module);
   auto* block = Builder(*module).makeBlock();
-  block->type = call->type;
   block->name = Name(std::string("__inlined_func$") + from->name.str);
   *action.callSite = block;
   // set up a locals mapping
@@ -191,6 +190,16 @@ static Expression* doInlining(Module* module, Function* into, InliningAction& ac
   auto* contents = ExpressionManipulator::copy(from->body, *module);
   updater.walk(contents);
   block->list.push_back(contents);
+  block->type = call->type;
+  // if the function returned a value, we just set the block containing the
+  // inlined code to have that type. or, if the function was void and
+  // contained void, that is fine too. a bad case is a void function in which
+  // we have unreachable code, so we would be replacing a void call with an
+  // unreachable; we need to handle
+  if (contents->type == unreachable && block->type == none) {
+    // make the block reachable by adding a break to it
+    block->list.push_back(builder.makeBreak(block->name));
+  }
   return block;
 }
 
diff --git a/test/passes/inlining-optimizing.txt b/test/passes/inlining-optimizing.txt
index e1f81e54f..19c580063 100644
--- a/test/passes/inlining-optimizing.txt
+++ b/test/passes/inlining-optimizing.txt
@@ -33,3 +33,11 @@
   (nop)
  )
 )
+(module
+ (type $0 (func (result i32)))
+ (type $1 (func))
+ (memory $0 0)
+ (func $main (type $0) (result i32)
+  (unreachable)
+ )
+)
diff --git a/test/passes/inlining-optimizing.wast b/test/passes/inlining-optimizing.wast
index 082c4e98a..4f4f348a6 100644
--- a/test/passes/inlining-optimizing.wast
+++ b/test/passes/inlining-optimizing.wast
@@ -76,4 +76,13 @@
     (drop (get_local $z))
   )
 )
+(module
+ (func $main (result i32)
+  (call $func_51)
+  (i32.const 0)
+ )
+ (func $func_51
+  (unreachable) ;; void function but having unreachable body, when inlined, type must be fixed
+ )
+)