global var init

cl/_testdata/fncall/out.ll

@@ -1,7 +1,7 @@
 ; ModuleID = 'main'
 source_filename = "main"
 
-@"init$guard" = external global ptr
+@"init$guard" = global ptr null
 
 define void @init() {
 _llgo_0:

cl/_testdata/varinit/out.ll

@@ -1,8 +1,8 @@
 ; ModuleID = 'main'
 source_filename = "main"
 
-@"init$guard" = external global ptr
-@a = external global ptr
+@"init$guard" = global ptr null
+@a = global ptr null
 
 define void @init() {
 _llgo_0:

cl/compile.go

@@ -53,6 +53,7 @@ func (p *context) compileGlobal(pkg llssa.Package, gbl *ssa.Global) llssa.Global
 		return g
 	}
 	g := pkg.NewVar(gbl.Name(), gbl.Type())
+	g.Init(p.prog.Null(g.Type))
 	p.glbs[gbl] = g
 	return g
 }

cl/compile_test.go

@@ -115,8 +115,8 @@ var a int
 `, `; ModuleID = 'foo'
 source_filename = "foo"
 
-@"init$guard" = external global ptr
-@a = external global ptr
+@"init$guard" = global ptr null
+@a = global ptr null
 
 define void @init() {
 _llgo_0:
@@ -142,7 +142,7 @@ func fn(a int, b float64) int {
 `, `; ModuleID = 'foo'
 source_filename = "foo"
 
-@"init$guard" = external global ptr
+@"init$guard" = global ptr null
 
 define void @init() {
 _llgo_0:

ssa/decl.go

@@ -46,11 +46,13 @@ type aGlobal struct {
 
 // A Global is a named Value holding the address of a package-level
 // variable.
-//
-// Pos() returns the position of the ast.ValueSpec.Names[*]
-// identifier.
 type Global = *aGlobal
 
+// Init initializes the global variable with the given value.
+func (g Global) Init(v Expr) {
+	g.impl.SetInitializer(v.impl)
+}
+
 // -----------------------------------------------------------------------------
 
 // Function represents the parameters, results, and code of a function

ssa/expr.go

@@ -43,6 +43,10 @@ func llvmValues(vals []Expr) []llvm.Value {
 
 // -----------------------------------------------------------------------------
 
+func (p Program) Null(t Type) Expr {
+	return Expr{llvm.ConstNull(t.ll), t}
+}
+
 func (p Program) BoolVal(v bool) Expr {
 	t := p.Bool()
 	var bv uint64

ssa/ssa_test.go

@@ -37,11 +37,15 @@ func assertPkg(t *testing.T, p Package, expected string) {
 func TestVar(t *testing.T) {
 	prog := NewProgram(nil)
 	pkg := prog.NewPackage("bar", "foo/bar")
-	pkg.NewVar("a", types.Typ[types.Int])
+	a := pkg.NewVar("a", types.Typ[types.Int])
+	a.Init(prog.Val(100))
+	b := pkg.NewVar("b", types.Typ[types.Int])
+	b.Init(a.Expr)
 	assertPkg(t, pkg, `; ModuleID = 'foo/bar'
 source_filename = "foo/bar"
 
-@a = external global i64
+@a = global i64 100
+@b = global i64 @a
 `)
 }