runtime: pointer 0x86e000 to unused region of span span.base()=0x87c000 span.limit=0x87de00 span.state=1
runtime: found in object at *(0x8640c0+0x1c)
object=0x8640c0 s.base()=0x864000 s.limit=0x865fe0 s.spanclass=16 s.elemsize=96 s.state=mSpanInUse
 *(object+0) = 0x1c
 *(object+4) = 0x0
 *(object+8) = 0x0
 *(object+12) = 0x0
 *(object+16) = 0x0
 *(object+20) = 0x0
 *(object+24) = 0x0
 *(object+28) = 0x86e000 <==
 *(object+32) = 0x0
 *(object+36) = 0x100
 *(object+40) = 0x874000
 *(object+44) = 0x14
 *(object+48) = 0x2000
 *(object+52) = 0x0
 *(object+56) = 0x0
 *(object+60) = 0x0
 *(object+64) = 0x0
 *(object+68) = 0x0
 *(object+72) = 0x0
 *(object+76) = 0x0
 *(object+80) = 0x0
 *(object+84) = 0x0
 *(object+88) = 0x0
 *(object+92) = 0x0
fatal error: found bad pointer in Go heap (incorrect use of unsafe or cgo?)

runtime stack:
runtime.throw({0x10e393, 0x3e})
	/usr/lib/go/src/runtime/panic.go:1047 +0x54 fp=0x839ecc sp=0x839eb8 pc=0x52208
runtime.badPointer(0x772f908c, 0x86e000, 0x8640c0, 0x1c)
	/usr/lib/go/src/runtime/mbitmap.go:373 +0x1d8 fp=0x839eec sp=0x839ecc pc=0x2429c
runtime.findObject(0x86e000, 0x8640c0, 0x1c)
	/usr/lib/go/src/runtime/mbitmap.go:416 +0x100 fp=0x839f04 sp=0x839eec pc=0x24490
runtime.scanobject(0x8640c0, 0x81a95c)
	/usr/lib/go/src/runtime/mgcmark.go:1338 +0x1ec fp=0x839f58 sp=0x839f04 pc=0x346f4
runtime.gcDrainN(0x81a95c, 0x8724)
	/usr/lib/go/src/runtime/mgcmark.go:1192 +0x2ac fp=0x839f7c sp=0x839f58 pc=0x3427c
runtime.gcAssistAlloc1(0x8000f0, 0x8724)
	/usr/lib/go/src/runtime/mgcmark.go:567 +0x188 fp=0x839fd8 sp=0x839f7c pc=0x32354
runtime.gcAssistAlloc.func1()
	/usr/lib/go/src/runtime/mgcmark.go:474 +0x50 fp=0x839fe8 sp=0x839fd8 pc=0x321bc
runtime.systemstack()
	/usr/lib/go/src/runtime/asm_mipsx.s:188 +0x7c fp=0x839fec sp=0x839fe8 pc=0x88224

goroutine 1 [GC assist marking]:
runtime.systemstack_switch()
	/usr/lib/go/src/runtime/asm_mipsx.s:149 +0x8 fp=0x8c2de8 sp=0x8c2de4 pc=0x88188
runtime.gcAssistAlloc(0x8000f0)
	/usr/lib/go/src/runtime/mgcmark.go:473 +0x464 fp=0x8c2e5c sp=0x8c2de8 pc=0x32018
runtime.mallocgc(0x3dc6c, 0x0, 0x0)
	/usr/lib/go/src/runtime/malloc.go:906 +0x1cc fp=0x8c2e9c sp=0x8c2e5c pc=0x1cf20
runtime.rawstring(0x3dc6c)
	/usr/lib/go/src/runtime/string.go:273 +0x5c fp=0x8c2eb0 sp=0x8c2e9c pc=0x74040
runtime.rawstringtmp(0x0, 0x3dc6c)
	/usr/lib/go/src/runtime/string.go:135 +0x88 fp=0x8c2ecc sp=0x8c2eb0 pc=0x73948
runtime.concatstrings(0x0, {0x8c2f30, 0x2, 0x2})
	/usr/lib/go/src/runtime/string.go:51 +0x118 fp=0x8c2f14 sp=0x8c2ecc pc=0x7327c
runtime.concatstring2(0x0, {0xbb8000, 0x3dc50}, {0xa704a0, 0x1c})
	/usr/lib/go/src/runtime/string.go:60 +0x84 fp=0x8c2f40 sp=0x8c2f14 pc=0x73528
main.main()
	/home/mwilson/sfsrc/local/mipstest/main.go:42 +0x15c fp=0x8c2fc0 sp=0x8c2f40 pc=0xe3cd4
runtime.main()
	/usr/lib/go/src/runtime/proc.go:250 +0x2b4 fp=0x8c2fec sp=0x8c2fc0 pc=0x55800
runtime.goexit()
	/usr/lib/go/src/runtime/asm_mipsx.s:617 +0x4 fp=0x8c2fec sp=0x8c2fec pc=0x8a538

goroutine 2 [force gc (idle)]:
runtime.gopark(0x10e8d8, 0x1a84f0, 0x11, 0x14, 0x1)
	/usr/lib/go/src/runtime/proc.go:363 +0x124 fp=0x824fd8 sp=0x824fcc pc=0x55d34
runtime.goparkunlock(...)
	/usr/lib/go/src/runtime/proc.go:369
runtime.forcegchelper()
	/usr/lib/go/src/runtime/proc.go:302 +0x110 fp=0x824fec sp=0x824fd8 pc=0x55b7c
runtime.goexit()
	/usr/lib/go/src/runtime/asm_mipsx.s:617 +0x4 fp=0x824fec sp=0x824fec pc=0x8a538
created by runtime.init.5
	/usr/lib/go/src/runtime/proc.go:290 +0x44

goroutine 3 [GC sweep wait]:
runtime.gopark(0x10e8d8, 0x1a85f0, 0xc, 0x14, 0x1)
	/usr/lib/go/src/runtime/proc.go:363 +0x124 fp=0x8257d0 sp=0x8257c4 pc=0x55d34
runtime.goparkunlock(...)
	/usr/lib/go/src/runtime/proc.go:369
runtime.bgsweep(0x818040)
	/usr/lib/go/src/runtime/mgcsweep.go:297 +0x16c fp=0x8257e4 sp=0x8257d0 pc=0x3c880
runtime.gcenable.func1()
	/usr/lib/go/src/runtime/mgc.go:178 +0x64 fp=0x8257ec sp=0x8257e4 pc=0x2ade4
runtime.goexit()
	/usr/lib/go/src/runtime/asm_mipsx.s:617 +0x4 fp=0x8257ec sp=0x8257ec pc=0x8a538
created by runtime.gcenable
	/usr/lib/go/src/runtime/mgc.go:178 +0xb4

goroutine 4 [GC scavenge wait]:
runtime.gopark(0x10e8d8, 0x1a86e0, 0xd, 0x14, 0x2)
	/usr/lib/go/src/runtime/proc.go:363 +0x124 fp=0x825fbc sp=0x825fb0 pc=0x55d34
runtime.goparkunlock(...)
	/usr/lib/go/src/runtime/proc.go:369
runtime.(*scavengerState).park(0x1a86e0)
	/usr/lib/go/src/runtime/mgcscavenge.go:389 +0x94 fp=0x825fd0 sp=0x825fbc pc=0x39a3c
runtime.bgscavenge(0x818040)
	/usr/lib/go/src/runtime/mgcscavenge.go:622 +0xb0 fp=0x825fe4 sp=0x825fd0 pc=0x3a360
runtime.gcenable.func2()
	/usr/lib/go/src/runtime/mgc.go:179 +0x64 fp=0x825fec sp=0x825fe4 pc=0x2ad70
runtime.goexit()
	/usr/lib/go/src/runtime/asm_mipsx.s:617 +0x4 fp=0x825fec sp=0x825fec pc=0x8a538
created by runtime.gcenable
	/usr/lib/go/src/runtime/mgc.go:179 +0x114

goroutine 5 [finalizer wait]:
runtime.gopark(0x10e8d8, 0x1b99cc, 0x10, 0x14, 0x1)
	/usr/lib/go/src/runtime/proc.go:363 +0x124 fp=0x824794 sp=0x824788 pc=0x55d34
runtime.goparkunlock(...)
	/usr/lib/go/src/runtime/proc.go:369
runtime.runfinq()
	/usr/lib/go/src/runtime/mfinal.go:180 +0x160 fp=0x8247ec sp=0x824794 pc=0x29b68
runtime.goexit()
	/usr/lib/go/src/runtime/asm_mipsx.s:617 +0x4 fp=0x8247ec sp=0x8247ec pc=0x8a538
created by runtime.createfing
	/usr/lib/go/src/runtime/mfinal.go:157 +0x94

goroutine 6 [GC worker (idle)]:
runtime.gopark(0x10e848, 0xafc6a8, 0x18, 0x14, 0x0)
	/usr/lib/go/src/runtime/proc.go:363 +0x124 fp=0x826790 sp=0x826784 pc=0x55d34
runtime.gcBgMarkWorker()
	/usr/lib/go/src/runtime/mgc.go:1235 +0x138 fp=0x8267ec sp=0x826790 pc=0x2dba4
runtime.goexit()
	/usr/lib/go/src/runtime/asm_mipsx.s:617 +0x4 fp=0x8267ec sp=0x8267ec pc=0x8a538
created by runtime.gcBgMarkStartWorkers
	/usr/lib/go/src/runtime/mgc.go:1159 +0x4c