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| author | Keith Randall <khr@golang.org> | 2021-08-20 10:19:28 -0700 |
|---|---|---|
| committer | Keith Randall <khr@golang.org> | 2021-08-23 17:51:41 +0000 |
| commit | 8486ced8b09f4425bfd85e09b021dc78f93aea08 (patch) | |
| tree | 1c778d44a91c3d0ab320d4d9aa8093cf7a29dc81 /src/cmd/compile/internal/noder | |
| parent | aeec6dbfe009f371021bddba13e2eb18e5d1a469 (diff) | |
| download | go-8486ced8b09f4425bfd85e09b021dc78f93aea08.tar.gz go-8486ced8b09f4425bfd85e09b021dc78f93aea08.zip | |
cmd/compile: copy captured dictionary var to local var
When starting a closure that needs a dictionary, copy the closure
variable to a local variable. This lets child closures capture that
dictionary variable correctly.
This is a better fix for #47684, which does not cause problems
like #47723.
Fixes #47723
Update #47684
Change-Id: Ib5d9ffc68a5142e28daa7d0d75683e7a35508540
Reviewed-on: https://go-review.googlesource.com/c/go/+/343871
Trust: Keith Randall <khr@golang.org>
Trust: Dan Scales <danscales@google.com>
Run-TryBot: Keith Randall <khr@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Dan Scales <danscales@google.com>
Diffstat (limited to 'src/cmd/compile/internal/noder')
| -rw-r--r-- | src/cmd/compile/internal/noder/stencil.go | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/src/cmd/compile/internal/noder/stencil.go b/src/cmd/compile/internal/noder/stencil.go index e8eee5290e..4ed1850597 100644 --- a/src/cmd/compile/internal/noder/stencil.go +++ b/src/cmd/compile/internal/noder/stencil.go @@ -1087,13 +1087,25 @@ func (subst *subster) node(n ir.Node) ir.Node { ir.FinishCaptureNames(oldfn.Pos(), saveNewf, newfn) newfn.ClosureVars = append(newfn.ClosureVars, subst.namelist(oldfn.ClosureVars)...) + // Copy that closure variable to a local one. + // Note: this allows the dictionary to be captured by child closures. + // See issue 47723. + ldict := ir.NewNameAt(x.Pos(), subst.info.gf.Sym().Pkg.Lookup(".dict")) + typed(types.Types[types.TUINTPTR], ldict) + ldict.Class = ir.PAUTO + ldict.Curfn = newfn + newfn.Dcl = append(newfn.Dcl, ldict) + as := ir.NewAssignStmt(x.Pos(), ldict, cdict) + as.SetTypecheck(1) + newfn.Body.Append(as) + // Create inst info for the instantiated closure. The dict // param is the closure variable for the dictionary of the // outer function. Since the dictionary is shared, use the // same entries for startSubDict, dictLen, dictEntryMap. cinfo := &instInfo{ fun: newfn, - dictParam: cdict, + dictParam: ldict, gf: subst.info.gf, gfInfo: subst.info.gfInfo, startSubDict: subst.info.startSubDict, @@ -1110,7 +1122,7 @@ func (subst *subster) node(n ir.Node) ir.Node { outerinfo := subst.info subst.info = cinfo // Make sure type of closure function is set before doing body. - newfn.Body = subst.list(oldfn.Body) + newfn.Body.Append(subst.list(oldfn.Body)...) subst.info = outerinfo subst.newf = saveNewf ir.CurFunc = saveNewf |