diff --git a/src/cmd/cgo/main.go b/src/cmd/cgo/main.go
index 5c44fb72f4..7d02ac3c54 100644
--- a/src/cmd/cgo/main.go
+++ b/src/cmd/cgo/main.go
@@ -170,35 +170,51 @@ func usage() {
 
 var ptrSizeMap = map[string]int64{
 	"386":      4,
+	"alpha":    8,
 	"amd64":    8,
 	"arm":      4,
 	"arm64":    8,
+	"m68k":     4,
 	"mips":     4,
 	"mipsle":   4,
 	"mips64":   8,
 	"mips64le": 8,
+	"nios2":    4,
+	"ppc":      4,
 	"ppc64":    8,
 	"ppc64le":  8,
+	"riscv":    4,
 	"riscv64":  8,
 	"s390":     4,
 	"s390x":    8,
+	"sh":       4,
+	"shbe":     4,
+	"sparc":    4,
 	"sparc64":  8,
 }
 
 var intSizeMap = map[string]int64{
 	"386":      4,
+	"alpha":    8,
 	"amd64":    8,
 	"arm":      4,
 	"arm64":    8,
+	"m68k":     4,
 	"mips":     4,
 	"mipsle":   4,
 	"mips64":   8,
 	"mips64le": 8,
+	"nios2":    4,
+	"ppc":      4,
 	"ppc64":    8,
 	"ppc64le":  8,
+	"riscv":    4,
 	"riscv64":  8,
 	"s390":     4,
 	"s390x":    8,
+	"sh":       4,
+	"shbe":     4,
+	"sparc":    4,
 	"sparc64":  8,
 }