fix relocation of global linkable variables, enable iostream module linking test

emscripten.py

@@ -481,11 +481,12 @@ def emscript(infile, settings, outfile, libraries=[], compiler_engine=None,
                       ''.join(['  var ' + g + '=+env.' + g + ';\n' for g in basic_float_vars])
     # In linkable modules, we need to add some explicit globals for global variables that can be linked and used across modules
     if settings.get('MAIN_MODULE') or settings.get('SIDE_MODULE'):
+      assert settings.get('TARGET_LE32'), 'TODO: support x86 target when linking modules (needs offset of 4 and not 8 here)'
       for key, value in forwarded_json['Variables']['globals'].iteritems():
         if value.get('linkable'):
-          init = str(forwarded_json['Variables']['indexedGlobals'][key])
-          if settings.get('SIDE_MODULE'): init = '(H_BASE+' + init + ')|0'
-          asm_global_vars += '  var %s=%s;\n' % (key, init)
+          init = forwarded_json['Variables']['indexedGlobals'][key] + 8 # 8 is Runtime.GLOBAL_BASE / STATIC_BASE
+          if settings.get('SIDE_MODULE'): init = '(H_BASE+' + str(init) + ')|0'
+          asm_global_vars += '  var %s=%s;\n' % (key, str(init))
 
     # sent data
     the_global = '{ ' + ', '.join(['"' + math_fix(s) + '": ' + s for s in fundamentals]) + ' }'

src/jsifier.js

@@ -1605,6 +1605,7 @@ function JSify(data, functionsOnly, givenFunctions) {
       if (phase == 'pre' && !Variables.generatedGlobalBase) {
         Variables.generatedGlobalBase = true;
         // Globals are done, here is the rest of static memory
+        assert((TARGET_LE32 && Runtime.GLOBAL_BASE == 8) || (TARGET_X86 && Runtime.GLOBAL_BASE == 4)); // this is assumed in e.g. relocations for linkable modules
         print('STATIC_BASE = ' + Runtime.GLOBAL_BASE + ';\n');
         print('STATICTOP = STATIC_BASE + ' + Runtime.alignMemory(Variables.nextIndexedOffset) + ';\n');
       }

tests/runner.py

@@ -10764,8 +10764,6 @@ f.close()
       finally:
         del os.environ['EMCC_FORCE_STDLIBS']
 
-      return # TODO
-
       # iostream usage in one and std::string in both
       test('iostream', r'''
         #include <iostream>