v1.5.8 - panic: runtime error: invalid memory address or nil pointer dereference

[chkp-roeym]

I'm trying to use this useful package with version v1.5.8, as the upcoming v1.5.9 requires Go version 1.18 or higher.

using the following code:
`//go:generate go run github.com/dmarkham/enumer -type=Role -json -yaml
type Role int

const (
A Role = iota + 1
B
)
`

got the following error:
`GOROOT=/usr/local/go #gosetup
GOPATH=/Users/roeym/go #gosetup
/usr/local/go/bin/go generate -run go run github.com/dmarkham/enumer -type=Role -json -yaml
panic: runtime error: invalid memory address or nil pointer dereference [recovered]
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x2 addr=0x0 pc=0x1008de354]

goroutine 11 [running]:
go/types.(*Checker).handleBailout(0x14000376800, 0x14000c73b98)
/usr/local/go/src/go/types/check.go:367 +0x9c
panic({0x1009d1e40?, 0x100b6ae40?})
/usr/local/go/src/runtime/panic.go:770 +0x124
go/types.(*StdSizes).Sizeof(0x0, {0x100a11a38, 0x100b6ddc0})
/usr/local/go/src/go/types/sizes.go:228 +0x314
go/types.(*Config).sizeof(...)
/usr/local/go/src/go/types/sizes.go:333
go/types.representableConst.func1({0x100a11a38?, 0x100b6ddc0?})
/usr/local/go/src/go/types/const.go:76 +0x9c
go/types.representableConst({0x100a13608, 0x100b63760}, 0x14000376800, 0x100b6ddc0, 0x14000e2db68)
/usr/local/go/src/go/types/const.go:92 +0x138
go/types.(*Checker).conversion.func1({0x100a12460?, 0x14000f02a10?}, 0x14000e2db68)
/usr/local/go/src/go/types/conversions.go:24 +0x74
go/types.(*Checker).conversion(0x14000376800, 0x14000e2db40, {0x100a12460, 0x14000f02a10})
/usr/local/go/src/go/types/conversions.go:44 +0x18c
go/types.(*Checker).callExpr(0x14000376800, 0x14000e2db40, 0x140006e8540)
/usr/local/go/src/go/types/call.go:224 +0xa54
go/types.(*Checker).exprInternal(0x14000376800, 0x0, 0x14000e2db40, {0x100a13200, 0x140006e8540}, {0x0, 0x0})
/usr/local/go/src/go/types/expr.go:1374 +0xd0
go/types.(*Checker).rawExpr(0x14000376800, 0x0, 0x14000e2db40, {0x100a13200?, 0x140006e8540?}, {0x0?, 0x0?}, 0x0)
/usr/local/go/src/go/types/expr.go:979 +0x12c
go/types.(*Checker).expr(0x14000376800, 0x14000a851a0?, 0x14000e2db40, {0x100a13200?, 0x140006e8540?})
/usr/local/go/src/go/types/expr.go:1513 +0x38
go/types.(*Checker).constDecl(0x14000376800, 0x14000a85260, {0x0, 0x0}, {0x100a13200, 0x140006e8540}, 0x0)
/usr/local/go/src/go/types/decl.go:488 +0x23c
go/types.(*Checker).objDecl(0x14000376800, {0x100a15818, 0x14000a85260}, 0x0)
/usr/local/go/src/go/types/decl.go:191 +0x84c
go/types.(*Checker).packageObjects(0x14000376800)
/usr/local/go/src/go/types/resolver.go:693 +0x468
go/types.(*Checker).checkFiles(0x14000376800, {0x140000a6240, 0x17, 0x17})
/usr/local/go/src/go/types/check.go:408 +0x164
go/types.(*Checker).Files(...)
/usr/local/go/src/go/types/check.go:372
golang.org/x/tools/go/packages.(*loader).loadPackage(0x1400014c000, 0x140004c3590)
/Users/roeym/git/saferx/saferx/vendor/golang.org/x/tools/go/packages/packages.go:1052 +0x870
golang.org/x/tools/go/packages.(*loader).loadRecursive.func1()
/Users/roeym/git/saferx/saferx/vendor/golang.org/x/tools/go/packages/packages.go:851 +0x178
sync.(*Once).doSlow(0x100739270?, 0x1400002cc00?)
/usr/local/go/src/sync/once.go:74 +0x100
sync.(*Once).Do(...)
/usr/local/go/src/sync/once.go:65
golang.org/x/tools/go/packages.(*loader).loadRecursive(0x0?, 0x10079f084?)
/Users/roeym/git/saferx/saferx/vendor/golang.org/x/tools/go/packages/packages.go:839 +0x50
golang.org/x/tools/go/packages.(*loader).refine.func2(0x0?)
/Users/roeym/git/saferx/saferx/vendor/golang.org/x/tools/go/packages/packages.go:774 +0x30
created by golang.org/x/tools/go/packages.(*loader).refine in goroutine 1
/Users/roeym/git/saferx/saferx/vendor/golang.org/x/tools/go/packages/packages.go:773 +0xaa4
exit status 2
role.go:5: running "go": exit status 1

Process finished with exit code 1
`

Thanks