diff --git a/Makefile b/Makefile
index b5e8992d..2805d72c 100644
--- a/Makefile
+++ b/Makefile
@@ -90,13 +90,13 @@ build/tgo: *.go
 	go build -o build/tgo -i .
 
 # Build IR with the Go compiler.
-build/%.o: src/examples/% src/examples/%/*.go build/tgo src/runtime/*.go build/runtime-$(TARGET)-combined.bc
+build/%.bc: src/examples/% src/examples/%/*.go build/tgo src/runtime/*.go build/runtime-$(TARGET)-combined.bc
 	./build/tgo $(TGOFLAGS) -runtime build/runtime-$(TARGET)-combined.bc -o $@ $(subst src/,,$<)
 
 # Compile and optimize bitcode file.
-#build/%.o: build/%.bc
-#	$(OPT) -coro-early -coro-split -coro-elide -Os -coro-cleanup -o $< $<
-#	$(LLC) -filetype=obj -o $@ $<
+build/%.o: build/%.bc
+	$(OPT) -Os -enable-coroutines -o $< $<
+	$(LLC) -filetype=obj -o $@ $<
 
 # Compile C sources for the runtime.
 build/%.bc: src/runtime/%.c src/runtime/*.h
diff --git a/compiler.go b/compiler.go
index dbb9b3c9..297fb454 100644
--- a/compiler.go
+++ b/compiler.go
@@ -1746,12 +1746,8 @@ func (c *Compiler) Optimize(optLevel, sizeLevel int) {
 	builder.PopulateFunc(funcPasses)
 
 	modPasses := llvm.NewPassManager()
-	modPasses.AddCoroEarlyPass()
-	modPasses.AddCoroSplitPass()
-	modPasses.AddCoroElidePass()
 	defer modPasses.Dispose()
 	builder.Populate(modPasses)
-	modPasses.AddCoroCleanupPass()
 
 	modPasses.Run(c.mod)
 }
diff --git a/main.go b/main.go
index 8d44f6a3..0e0ad398 100644
--- a/main.go
+++ b/main.go
@@ -55,7 +55,7 @@ func Compile(pkgName, runtimePath, outpath, target string, printIR, dumpSSA bool
 	if err := c.Verify(); err != nil {
 		return err
 	}
-	c.Optimize(2, 1) // -O2 -Os
+	//c.Optimize(2, 1) // -O2 -Os
 	if err := c.Verify(); err != nil {
 		return err
 	}