Simplify app to more match Roc's controlled environment

linker/tests/Makefile

@@ -1,6 +1,6 @@
 SHARED_ARGS = -fPIC -ffunction-sections
 
-all: platform
+all: platform app.o
 
 platform: platform.o linker.ld libapp.so
 	$(CXX) $(SHARED_ARGS) -L. -lapp -fPIE -T linker.ld -o $@ $<
@@ -8,6 +8,9 @@ platform: platform.o linker.ld libapp.so
 platform.o: platform.cc
 	$(CXX) $(SHARED_ARGS) -c -o $@ $^
 
+app.o: app.cc
+	$(CXX) -fPIC -c -o $@ $^
+
 libapp.so: app.cc
 	$(CXX) $(SHARED_ARGS) -shared -o $@ $^
 

linker/tests/app.cc

@@ -1,8 +1,3 @@
-#include <iostream>
-
-void init() { std::cout << "Application initializing...\n"; }
-void app() { std::cout << "Hello World from the application\n"; }
-int cleanup() {
-  std::cout << "Cleaning up application...\n";
-  return 0;
-}
+const char* init() { return "Application initializing...\n"; }
+const char* app() { return "Hello World from the application\n"; }
+const char* cleanup() { return "Cleaning up application...\n"; }

linker/tests/platform.cc

@@ -1,12 +1,12 @@
 #include <iostream>
 
-void init();
-void app();
-int cleanup();
+const char* init();
+const char* app();
+const char* cleanup();
 
-void func_section_1() { init(); }
+void func_section_1() { std::cout << init(); }
 
-void func_section_2() { app(); }
+void func_section_2() { std::cout << app(); }
 
 int main() {
   std::cout << "Hello World from the platform\n";
@@ -15,7 +15,8 @@ int main() {
 
   // Long term we want to support this case cause if it accidentially arises, we
   // don't want bugs.
-  int (*func_pointer)();
+  const char* (*func_pointer)();
   func_pointer = &cleanup;
-  return (*func_pointer)();
+  std::cout << (*func_pointer)();
+  return 0;
 }