From af1c29c1c1051a26de4cc72454827dd01e578b45 Mon Sep 17 00:00:00 2001 From: Josh Bleecher Snyder Date: Sun, 13 Mar 2016 10:13:03 -0700 Subject: [PATCH] cmd/internal/obj: sort relocs by off when printing This makes the output of compiling with -S more stable in the face of unimportant variation in the order in which relocs are generated. It is also more pleasant to read the relocs when they are sorted. Also, do some minor cleanup. For #14786 Change-Id: Id92020b13fd21777dfb5b29c2722c3b2eb27001b Reviewed-on: https://go-review.googlesource.com/20641 Reviewed-by: Matthew Dempsky --- src/cmd/internal/obj/objfile.go | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) diff --git a/src/cmd/internal/obj/objfile.go b/src/cmd/internal/obj/objfile.go index fff2b9d14e..c2a55aa2b0 100644 --- a/src/cmd/internal/obj/objfile.go +++ b/src/cmd/internal/obj/objfile.go @@ -104,6 +104,7 @@ import ( "fmt" "log" "path/filepath" + "sort" "strings" ) @@ -417,11 +418,9 @@ func writesym(ctxt *Link, b *Biobuf, s *LSym) { i += 16 } - var r *Reloc - var name string - for i := 0; i < len(s.R); i++ { - r = &s.R[i] - name = "" + sort.Sort(relocByOff(s.R)) // generate stable output + for _, r := range s.R { + name := "" if r.Sym != nil { name = r.Sym.Name } @@ -562,3 +561,10 @@ func wrsym(b *Biobuf, s *LSym) { wrstring(b, s.Name) wrint(b, int64(s.Version)) } + +// relocByOff sorts relocations by their offsets. +type relocByOff []Reloc + +func (x relocByOff) Len() int { return len(x) } +func (x relocByOff) Less(i, j int) bool { return x[i].Off < x[j].Off } +func (x relocByOff) Swap(i, j int) { x[i], x[j] = x[j], x[i] }