diff --git a/cmd/callgraph/main.go b/cmd/callgraph/main.go
index 7284c4b386..2e09bc446b 100644
--- a/cmd/callgraph/main.go
+++ b/cmd/callgraph/main.go
@@ -187,7 +187,7 @@ func doCallgraph(dir, gopath, algo, format string, tests bool, args []string) er
 	}
 
 	// Create and build SSA-form program representation.
-	prog, pkgs := ssautil.Packages(initial, 0)
+	prog, pkgs := ssautil.AllPackages(initial, 0)
 	prog.Build()
 
 	// -- call graph construction ------------------------------------------
diff --git a/cmd/ssadump/main.go b/cmd/ssadump/main.go
index b978249503..fee931b1c3 100644
--- a/cmd/ssadump/main.go
+++ b/cmd/ssadump/main.go
@@ -131,7 +131,7 @@ func doMain() error {
 	}
 
 	// Create SSA-form program representation.
-	prog, pkgs := ssautil.Packages(initial, mode)
+	prog, pkgs := ssautil.AllPackages(initial, mode)
 
 	for i, p := range pkgs {
 		if p == nil {
diff --git a/go/ssa/example_test.go b/go/ssa/example_test.go
index 6ca777686b..c33b6d624c 100644
--- a/go/ssa/example_test.go
+++ b/go/ssa/example_test.go
@@ -155,8 +155,8 @@ func ExampleLoadWholeProgram() {
 		log.Fatal(err)
 	}
 
-	// Create SSA packages for all well-typed packages.
-	prog, pkgs := ssautil.Packages(initial, ssa.PrintPackages)
+	// Create SSA packages for well-typed packages and their dependencies.
+	prog, pkgs := ssautil.AllPackages(initial, ssa.PrintPackages)
 	_ = pkgs
 
 	// Build SSA code for the whole program.
diff --git a/go/ssa/ssautil/load.go b/go/ssa/ssautil/load.go
index 03068d50b2..72710becf8 100644
--- a/go/ssa/ssautil/load.go
+++ b/go/ssa/ssautil/load.go
@@ -16,19 +16,52 @@ import (
 	"golang.org/x/tools/go/ssa"
 )
 
-// Packages creates an SSA program for a set of packages loaded from
-// source syntax using the golang.org/x/tools/go/packages.Load function.
-// It creates and returns an SSA package for each well-typed package in
-// the initial list. The resulting list of packages has the same length
-// as initial, and contains a nil if SSA could not be constructed for
-// the corresponding initial package.
+// Packages creates an SSA program for a set of packages.
 //
-// Code for bodies of functions is not built until Build is called
-// on the resulting Program.
+// The packages must have been loaded from source syntax using the
+// golang.org/x/tools/go/packages.Load function in LoadSyntax or
+// LoadAllSyntax mode.
+//
+// Packages creates an SSA package for each well-typed package in the
+// initial list, plus all their dependencies. The resulting list of
+// packages corresponds to the list of initial packages, and may contain
+// a nil if SSA code could not be constructed for the corresponding initial
+// package due to type errors.
+//
+// Code for bodies of functions is not built until Build is called on
+// the resulting Program. SSA code is constructed only for the initial
+// packages with well-typed syntax trees.
 //
 // The mode parameter controls diagnostics and checking during SSA construction.
 //
 func Packages(initial []*packages.Package, mode ssa.BuilderMode) (*ssa.Program, []*ssa.Package) {
+	return doPackages(initial, mode, false)
+}
+
+// AllPackages creates an SSA program for a set of packages plus all
+// their dependencies.
+//
+// The packages must have been loaded from source syntax using the
+// golang.org/x/tools/go/packages.Load function in LoadAllSyntax mode.
+//
+// AllPackages creates an SSA package for each well-typed package in the
+// initial list, plus all their dependencies. The resulting list of
+// packages corresponds to the list of intial packages, and may contain
+// a nil if SSA code could not be constructed for the corresponding
+// initial package due to type errors.
+//
+// Code for bodies of functions is not built until Build is called on
+// the resulting Program. SSA code is constructed for all packages with
+// well-typed syntax trees.
+//
+// The mode parameter controls diagnostics and checking during SSA construction.
+//
+func AllPackages(initial []*packages.Package, mode ssa.BuilderMode) (*ssa.Program, []*ssa.Package) {
+	return doPackages(initial, mode, true)
+}
+
+func doPackages(initial []*packages.Package, mode ssa.BuilderMode, deps bool) (*ssa.Program, []*ssa.Package) {
+
 	var fset *token.FileSet
 	if len(initial) > 0 {
 		fset = initial[0].Fset
@@ -36,10 +69,19 @@ func Packages(initial []*packages.Package, mode ssa.BuilderMode) (*ssa.Program,
 
 	prog := ssa.NewProgram(fset, mode)
 
+	isInitial := make(map[*packages.Package]bool, len(initial))
+	for _, p := range initial {
+		isInitial[p] = true
+	}
+
 	ssamap := make(map[*packages.Package]*ssa.Package)
 	packages.Visit(initial, nil, func(p *packages.Package) {
 		if p.Types != nil && !p.IllTyped {
-			ssamap[p] = prog.CreatePackage(p.Types, p.Syntax, p.TypesInfo, true)
+			var files []*ast.File
+			if deps || isInitial[p] {
+				files = p.Syntax
+			}
+			ssamap[p] = prog.CreatePackage(p.Types, files, p.TypesInfo, true)
 		}
 	})
 
diff --git a/go/ssa/ssautil/load_test.go b/go/ssa/ssautil/load_test.go
index 2885ed3965..4724e33e8d 100644
--- a/go/ssa/ssautil/load_test.go
+++ b/go/ssa/ssautil/load_test.go
@@ -104,3 +104,17 @@ func TestBuildPackage_MissingImport(t *testing.T) {
 		t.Fatal("BuildPackage succeeded unexpectedly")
 	}
 }
+
+func TestIssue28106(t *testing.T) {
+	// In go1.10, go/packages loads all packages from source, not
+	// export data, but does not type check function bodies of
+	// imported packages. This test ensures that we do not attempt
+	// to run the SSA builder on functions without type information.
+	cfg := &packages.Config{Mode: packages.LoadSyntax}
+	pkgs, err := packages.Load(cfg, "runtime")
+	if err != nil {
+		t.Fatal(err)
+	}
+	prog, _ := ssautil.Packages(pkgs, 0)
+	prog.Build() // no crash
+}