cmd/compile: closure miscompilation in gopher-lua benchmark

[mknyszek]

CL 484860 broke the x/benchmarks builder: https://build.golang.org/?repo=golang.org%2fx%2fbenchmarks

Failure: https://build.golang.org/log/11803116ada45552b52ed62dd86f4255cdba5d87

What's happening is this call produces a closure that appears to be inlined into a compiler-generated init function. The closure it produces later gets installed here.

The end result is this function ends up dereferencing a nil pointer.

Reproducer instructions:

git clone https://go.googlesource.com/benchmarks
go build ./benchmarks/sweet/benchmarks/gopher-lua
./gopher-lua k-nucleotide.txt input.txt

k-nucleotide.txt
input.txt

[mknyszek]

CC @golang/compiler

Perhaps specifically @thanm @mdempsky?

[mknyszek]

Revert: https://go.dev/cl/485498

[thanm]

I'll take a look tomorrow.