Crash in garbage collector when heap is resized

[vidya88]

@asahi3g commented on Mar 12

To Reproduce

package main
func fooB(path str) {
	var ss []i32
	var INIT_HEAP_SIZE i32 = 32 * (1 << 20) // TODO : should be tested against real cx/config.go::INIT_HEAP_SIZE
	for i := 0; i < INIT_HEAP_SIZE; i++ {
		ss = append(ss, 1)
	}
}
func fooA(path str, filename str, s f32, r f32) {
	fooB(sprintf("%s/%s", path, filename))
}
func main()() {
	fooA("test", "A", 1.0, 2.0)
}

Expected behavior

Screenshots

error: tests/pending_20.cx:7, CX_RUNTIME_ERROR, runtime error: index out of range
===Callstack===
>>> fooB()
Inputs
error: tests/pending_20.cx:7, CX_RUNTIME_ERROR, runtime error: slice bounds out of range
===Callstack===
>>> fooB()
Inputs
error: tests/pending_20.cx:7, CX_RUNTIME_ERROR, runtime error: slice bounds out of range
===Callstack===
>>> fooB()
Inputs
panic: runtime error: index out of range [recovered]
	panic: runtime error: slice bounds out of range [recovered]
	panic: runtime error: slice bounds out of range [recovered]
	panic: runtime error: slice bounds out of range

goroutine 1 [running, locked to thread]:
github.com/skycoin/cx/cx.ReadStr(0x14, 0xc00019b680, 0x9bef14, 0x3)
	/home/reash/go/src/github.com/skycoin/cx/cx/op.go:494 +0x244
github.com/skycoin/cx/cx.getNonCollectionValue(0x14, 0xc00019b680, 0xc00019b680, 0x9bef14, 0x3, 0x9ae6c0, 0x14)
	/home/reash/go/src/github.com/skycoin/cx/cx/utilities.go:853 +0x8ad
github.com/skycoin/cx/cx.GetPrintableValue(0x14, 0xc00019b680, 0xc0005600a8, 0x2)
	/home/reash/go/src/github.com/skycoin/cx/cx/utilities.go:963 +0x7d6
github.com/skycoin/cx/cx.(*CXProgram).PrintStack(0xc0004de000)
	/home/reash/go/src/github.com/skycoin/cx/cx/utilities.go:53 +0x2b1
github.com/skycoin/cx/cx.runtimeErrorInfo(0x9547e0, 0xd83b40, 0xd83b01, 0x5)
	/home/reash/go/src/github.com/skycoin/cx/cx/utilities.go:814 +0x2ef
github.com/skycoin/cx/cx.RuntimeError()
	/home/reash/go/src/github.com/skycoin/cx/cx/utilities.go:841 +0x16d
panic(0x9547e0, 0xd83b40)
	/usr/local/go/src/runtime/panic.go:522 +0x1b5
github.com/skycoin/cx/cx.ReadStr(0x14, 0xc00019b680, 0x9bef14, 0x3)
	/home/reash/go/src/github.com/skycoin/cx/cx/op.go:494 +0x244
github.com/skycoin/cx/cx.getNonCollectionValue(0x14, 0xc00019b680, 0xc00019b680, 0x9bef14, 0x3, 0x9ae6c0, 0x14)
	/home/reash/go/src/github.com/skycoin/cx/cx/utilities.go:853 +0x8ad
github.com/skycoin/cx/cx.GetPrintableValue(0x14, 0xc00019b680, 0xc000560838, 0x2)
	/home/reash/go/src/github.com/skycoin/cx/cx/utilities.go:963 +0x7d6
github.com/skycoin/cx/cx.(*CXProgram).PrintStack(0xc0004de000)
	/home/reash/go/src/github.com/skycoin/cx/cx/utilities.go:53 +0x2b1
github.com/skycoin/cx/cx.runtimeErrorInfo(0x9547e0, 0xd83b40, 0xd83b01, 0x5)
	/home/reash/go/src/github.com/skycoin/cx/cx/utilities.go:814 +0x2ef
github.com/skycoin/cx/cx.RuntimeError()
	/home/reash/go/src/github.com/skycoin/cx/cx/utilities.go:841 +0x16d
panic(0x9547e0, 0xd83b40)
	/usr/local/go/src/runtime/panic.go:522 +0x1b5
github.com/skycoin/cx/cx.ReadStr(0x14, 0xc00019b680, 0x9bef14, 0x3)
	/home/reash/go/src/github.com/skycoin/cx/cx/op.go:494 +0x244
github.com/skycoin/cx/cx.getNonCollectionValue(0x14, 0xc00019b680, 0xc00019b680, 0x9bef14, 0x3, 0x9ae6c0, 0x14)
	/home/reash/go/src/github.com/skycoin/cx/cx/utilities.go:853 +0x8ad
github.com/skycoin/cx/cx.GetPrintableValue(0x14, 0xc00019b680, 0xc000826fc8, 0x2)
	/home/reash/go/src/github.com/skycoin/cx/cx/utilities.go:963 +0x7d6
github.com/skycoin/cx/cx.(*CXProgram).PrintStack(0xc0004de000)
	/home/reash/go/src/github.com/skycoin/cx/cx/utilities.go:53 +0x2b1
github.com/skycoin/cx/cx.runtimeErrorInfo(0x9547e0, 0xd83b30, 0xd83b01, 0x5)
	/home/reash/go/src/github.com/skycoin/cx/cx/utilities.go:814 +0x2ef
github.com/skycoin/cx/cx.RuntimeError()
	/home/reash/go/src/github.com/skycoin/cx/cx/utilities.go:841 +0x16d
panic(0x9547e0, 0xd83b30)
	/usr/local/go/src/runtime/panic.go:522 +0x1b5
github.com/skycoin/cx/cx.MarkAndCompact()
	/home/reash/go/src/github.com/skycoin/cx/cx/op.go:196 +0x50c
github.com/skycoin/cx/cx.AllocateSeq(0x200011, 0x4)
	/home/reash/go/src/github.com/skycoin/cx/cx/op.go:263 +0x8a
github.com/skycoin/cx/cx.SliceResize(0x10003f0010003f, 0x40001, 0x4, 0x100018)
	/home/reash/go/src/github.com/skycoin/cx/cx/utilities.go:672 +0x361
github.com/skycoin/cx/cx.SliceAppend(0x10003f0010003f, 0xc0002c8018, 0x4, 0x1fffec, 0xc000827540)
	/home/reash/go/src/github.com/skycoin/cx/cx/utilities.go:701 +0x54
github.com/skycoin/cx/cx.opAppend(0xc000079360, 0x14)
	/home/reash/go/src/github.com/skycoin/cx/cx/op_und.go:405 +0x219
github.com/skycoin/cx/cx.init.1.func1(0xc0004de000)
	/home/reash/go/src/github.com/skycoin/cx/cx/opcodes_bare.go:1476 +0x1664
github.com/skycoin/cx/cx.init.3.func1(0xc0004de000)
	/home/reash/go/src/github.com/skycoin/cx/cx/opcodes_extra.go:780 +0x14c6
github.com/skycoin/cx/cx.(*CXCall).ccall(0xc0001c2030, 0xc0004de000, 0x0, 0x0)
	/home/reash/go/src/github.com/skycoin/cx/cx/execute.go:310 +0x331
github.com/skycoin/cx/cx.(*CXProgram).Run(0xc0004de000, 0x9bed01, 0xc0005618c8, 0xffffffffffffffff, 0x0, 0x0)
	/home/reash/go/src/github.com/skycoin/cx/cx/execute.go:119 +0x117
github.com/skycoin/cx/cx.(*CXProgram).RunCompiled(0xc0004de000, 0x0, 0x0, 0x0, 0x0, 0xc000180e70, 0x0)
	/home/reash/go/src/github.com/skycoin/cx/cx/execute.go:201 +0x238
main.main()
	/home/reash/go/src/github.com/skycoin/cx/cxgo/cxgo.nn.go:8885 +0xce2

Desktop:

• OS: Linux
• CX Version : 0.6.1, d8775bf

[vidya88]

@amherag commented on Sep 9

This seems to be fixed now. For the record, I ran this code (which uses 2 Mb of heap memory as INIT_HEAP_SIZE; I also tried with 4 Mb and it worked, which means that CX is correctly expanding the heap size beyond INIT_HEAP_SIZE).

package main
func fooB(path str) {
	var ss []i32
	var INIT_HEAP_SIZE i32 = 2097152
	for i := 0; i < INIT_HEAP_SIZE; i++ {
		ss = append(ss, 1)
	}
}
func fooA(path str, filename str, s f32, r f32) {
	fooB(sprintf("%s/%s", path, filename))
}
func main()() {
	fooA("test", "A", 1.0, 2.0)
}

[SkycoinSynth]

Resolved