panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x0 pc=0x5f155b]

goroutine 29 [running]:
github.com/google/syzkaller/prog.(*GroupArg).Type(0x0, 0xc00bf7fbc0, 0xd13d40)
	<autogenerated>:1 +0x2b
github.com/google/syzkaller/prog.calcChecksumsCall.func1(0xd13d00, 0x0, 0x0)
	/syzkaller/gopath/src/github.com/google/syzkaller/prog/checksum.go:34 +0x47
github.com/google/syzkaller/prog.foreachArgImpl(0xd13d00, 0xc000085ae0, 0xc009f7d180, 0xc00bf89848)
	/syzkaller/gopath/src/github.com/google/syzkaller/prog/analysis.go:129 +0x119
github.com/google/syzkaller/prog.foreachArgImpl(0xd13d40, 0xc00031da40, 0xc009f7d180, 0xc00d1ee848)
	/syzkaller/gopath/src/github.com/google/syzkaller/prog/analysis.go:156 +0x656
github.com/google/syzkaller/prog.ForeachArg(0xc0000ad5c0, 0xc00bf89848)
	/syzkaller/gopath/src/github.com/google/syzkaller/prog/analysis.go:122 +0xdd
github.com/google/syzkaller/prog.calcChecksumsCall(0xc0000ad5c0, 0xc0000ad540, 0x0)
	/syzkaller/gopath/src/github.com/google/syzkaller/prog/checksum.go:33 +0xbe
github.com/google/syzkaller/prog.(*Prog).SerializeForExec(0xc0000ad500, 0x82c600000, 0x400000, 0x400000, 0xc00b7955f0, 0xc000102000, 0xc002d9c6c8)
	/syzkaller/gopath/src/github.com/google/syzkaller/prog/encodingexec.go:75 +0x14c
github.com/google/syzkaller/pkg/ipc.(*Env).Exec(0xc009fe86c0, 0xc0000a84e0, 0xc0000ad500, 0xc00002e000, 0xc00003fd50, 0x4ae762, 0x4ad96a, 0x3, 0x8, 0xc0000a2000)
	/syzkaller/gopath/src/github.com/google/syzkaller/pkg/ipc/ipc.go:255 +0x62
main.(*Proc).executeRaw(0xc009f7d080, 0xc0000a84e0, 0xc0000ad500, 0x2, 0x0)
	/syzkaller/gopath/src/github.com/google/syzkaller/syz-fuzzer/proc.go:290 +0x214
main.(*Proc).execute(0xc009f7d080, 0xc0000a84e0, 0xc0000ad500, 0x7, 0x2, 0x0)
	/syzkaller/gopath/src/github.com/google/syzkaller/syz-fuzzer/proc.go:249 +0x6a
main.(*Proc).loop(0xc009f7d080)
	/syzkaller/gopath/src/github.com/google/syzkaller/syz-fuzzer/proc.go:76 +0x143
created by main.main
	/syzkaller/gopath/src/github.com/google/syzkaller/syz-fuzzer/fuzzer.go:289 +0x1481


FreeBSD/amd64 (ci-freebsd-main-6.c.syzkaller.internal) (ttyu0)

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