Merge branch 'feature/wasm-obj'

README.md

@@ -95,6 +95,7 @@ Command line options:
   * `-o <filename>`: Set output filename (default: `a.wasm`)
   * `-I <path>`:     Add include path
   * `-D <label>(=value)`:  Define macro
+  * `-c`:            Output object file
   * `--entry-point=func_name`:  Specify entry point (default: `_start`)
   * `-e func_name,...`:  Export function names (comma separated)
   * `--stack-size=<size>`:  Set stack size (default: 8192)

src/cc/frontend/cc_misc.c

@@ -166,6 +166,7 @@ void construct_initial_value(const Type *type, const Initializer *init,
     if (init->kind == IK_SINGLE) {
       Expr *e = strip_cast(init->single);
       if (e->kind == EX_STR && is_char_type(type->pa.ptrof, e->str.kind)) {
+        assert(vtable->emit_string != NULL);
         (*vtable->emit_string)(ud, e, type_size(type));
         break;
       }
@@ -198,6 +199,7 @@ void construct_initial_value(const Type *type, const Initializer *init,
         if (mem_init != NULL || !sinfo->is_union) {
           int align = align_size(member->type);
           if (offset % align != 0) {
+            assert(vtable->emit_align != NULL);
             (*vtable->emit_align)(ud, align);
             offset = ALIGN(offset, align);
           }

src/cc/frontend/fe_misc.c

@@ -1408,6 +1408,17 @@ static void check_func_return(Function *func) {
   Type *type = func->type;
   Type *rettype = type->func.ret;
   const Token *rbrace = func->body_block->block.rbrace;
+
+  static const Name *main_name;
+  if (main_name == NULL)
+    main_name = alloc_name("main", NULL, false);
+  if (equal_name(func->name, main_name)) {
+    if (rettype->kind == TY_VOID) {
+      // Force return type to `int' for `main' function.
+      type->func.ret = rettype = &tyInt;
+    }
+  }
+
   if (func->flag & FUNCF_NORETURN) {
     if (rettype->kind != TY_VOID) {
       parse_error(PE_WARNING, rbrace, "`noreturn' function should not return value");
@@ -1420,7 +1431,7 @@ static void check_func_return(Function *func) {
   } else if (rettype->kind != TY_VOID && !(func->body_block->reach & REACH_STOP)) {
     Vector *stmts = func->body_block->block.stmts;
     if (stmts->len == 0 || ((Stmt*)stmts->data[stmts->len - 1])->kind != ST_ASM) {
-      if (equal_name(func->name, alloc_name("main", NULL, false))) {
+      if (equal_name(func->name, main_name)) {
         // Return 0 if `return` statement is omitted in `main` function.
         if (!is_fixnum(rettype->kind) || rettype->fixnum.kind != FX_INT) {
           parse_error(PE_WARNING, rbrace, "`main' return type should be `int'");