code review 183140043: all: merge dev.garbage (d1238958d4ae) into default branch

src/runtime/proc.go

 // Copyright 2014 The Go Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
 package runtime
 
 import "unsafe"
 
 func runtime_init()
 func main_init()
@@ skipping 163 matching lines @@
         // Delicate dance: the semaphore implementation calls
         // acquireSudog, acquireSudog calls new(sudog),
         // new calls malloc, malloc can call the garbage collector,
         // and the garbage collector calls the semaphore implementation
         // in stoptheworld.
         // Break the cycle by doing acquirem/releasem around new(sudog).
         // The acquirem/releasem increments m.locks during new(sudog),
         // which keeps the garbage collector from being invoked.
         mp := acquirem()
         p := new(sudog)
+        if p.elem != nil {
+                gothrow("acquireSudog: found p.elem != nil after new")
+        }
         releasem(mp)
         return p
 }
 
 //go:nosplit
 func releaseSudog(s *sudog) {
         if s.elem != nil {
                 gothrow("runtime: sudog with non-nil elem")
         }
         if s.selectdone != nil {
@@ skipping 63 matching lines @@
         if readgstatus(gp) == _Gidle {
                 gothrow("allgadd: bad status Gidle")
         }
 
         lock(&allglock)
         allgs = append(allgs, gp)
         allg = &allgs[0]
         allglen = uintptr(len(allgs))
         unlock(&allglock)
 }