feat: implement baremetal GC

fix: pthread gc

fix: xiao-esp32c3 symbol

refactor: use clite memset instead of linking

fix: stack top symbol

internal/build/build.go

@@ -753,7 +753,6 @@ func compileExtraFiles(ctx *context, verbose bool) ([]string, error) {
 }
 
 func linkMainPkg(ctx *context, pkg *packages.Package, pkgs []*aPackage, global llssa.Package, outputPath string, verbose bool) error {
-
 	needRuntime := false
 	needPyInit := false
 	pkgsMap := make(map[*packages.Package]*aPackage, len(pkgs))
@@ -998,6 +997,10 @@ define weak void @runtime.init() {
   ret void
 }
 
+define weak void @initGC() {
+  ret void
+}
+
 ; TODO(lijie): workaround for syscall patch
 define weak void @"syscall.init"() {
   ret void
@@ -1009,6 +1012,7 @@ define weak void @"syscall.init"() {
 _llgo_0:
   store i32 %%0, ptr @__llgo_argc, align 4
   store ptr %%1, ptr @__llgo_argv, align 8
+  call void @initGC()
   %s
   %s
   %s