diff options
Diffstat (limited to 'prog/any.go')
| -rw-r--r-- | prog/any.go | 26 |
1 files changed, 14 insertions, 12 deletions
diff --git a/prog/any.go b/prog/any.go index bb80eaa38..16a309c90 100644 --- a/prog/any.go +++ b/prog/any.go @@ -236,18 +236,19 @@ func (target *Target) squashResult(arg *ResultArg, elems *[]Arg) { } func (target *Target) squashGroup(arg *GroupArg, elems *[]Arg) { - var pad uint64 - if typ, ok := arg.Type().(*StructType); ok && typ.Varlen() && typ.AlignAttr != 0 { - var fieldsSize uint64 - for _, fld := range arg.Inner { - fieldsSize += fld.Size() - } - if fieldsSize%typ.AlignAttr != 0 { - pad = typ.AlignAttr - fieldsSize%typ.AlignAttr - } + overlayField := 0 + if typ, ok := arg.Type().(*StructType); ok { + overlayField = typ.OverlayField } - var bitfield uint64 - for _, fld := range arg.Inner { + var bitfield, fieldsSize uint64 + for i, fld := range arg.Inner { + if i != 0 && i == overlayField { + // We don't squash overlay fields. + // Theoretically we could produce a squashed struct with overlay as well, + // but it's quite complex to do. + break + } + fieldsSize += fld.Size() // Squash bitfields separately. if fld.Type().IsBitfield() { bfLen := fld.Type().BitfieldLength() @@ -271,7 +272,8 @@ func (target *Target) squashGroup(arg *GroupArg, elems *[]Arg) { } target.squashPtrImpl(fld, elems) } - if pad != 0 { + // Add padding either due to dynamic alignment or overlay fields. + if pad := arg.Size() - fieldsSize; pad != 0 { elem := target.ensureDataElem(elems) elem.data = append(elem.Data(), make([]byte, pad)...) } |