runtime: find uses of int32 that should be uintptr #6046
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I will never figure out how "Update issue xxx" works, because it never does. findnull and findnullw: https://golang.org/cl/12520043 maxstring and concatstring: https://golang.org/cl/12519044 |
On the topic of this general awfulness, would it be possible to change 6c et al. to complain about integer operations mixing different signs and/or types? There's a gcc flag for that that we're slowly turning on but there's no way at the moment to do it in the runtime's C code. Since our C compiler is used only there, let's be strict. |
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Owner changed to @robpike. Status changed to Started. |
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I suspect this is obsolete.. |
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Yes, I just verified they've been fixed. |
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In src/pkg/runtime/strings.goc, findnull uses an int32: int32 runtime·findnull(byte *s) { int32 l; if(s == nil) return 0; for(l=0; s[l]!=0; l++) ; return l; } And that is called by: String runtime·gostring(byte *str) { intgo l; String s; l = runtime·findnull(str); s = gostringsize(l); runtime·memmove(s.str, str, l); return s; } Which means: package main /* */ import "C" import "unsafe" func main() { println("pre-make") buf := make([]byte, 1<<31 + 2) println("pre-set") for i := range buf { buf[i] = 'a' } buf[len(buf)-1] = 0 println("pre-gostring") println(len(C.GoString((*C.char)(unsafe.Pointer(&buf[0]))))) } $ go run x.go pre-make pre-set pre-gostring unexpected fault address 0xc190022000 fatal error: fault [signal 0xa code=0x2 addr=0xc190022000 pc=0x401b7de] goroutine 1 [running]: runtime.throw(0x405e0dc) /Users/bradfitz/go/src/pkg/runtime/panic.c:498 +0x69 fp=0x4210e80 runtime.sigpanic() /Users/bradfitz/go/src/pkg/runtime/os_darwin.c:446 +0x1ed fp=0x4210e98 runtime.findnull(0xc210022000) /Users/bradfitz/go/src/pkg/runtime/string.goc:21 +0x1e fp=0x4210ea8 runtime.gostring(0x4210f00, 0xc210022000) /Users/bradfitz/go/src/pkg/runtime/string.goc:66 +0x27 fp=0x4210ee0 main._Cfunc_GoString(0xc210022000, 0xc, 0x80000002) command-line-arguments/_obj/_cgo_defun.c:10 +0x31 fp=0x4210ef8 main.main() /Users/bradfitz/x.go:19 +0x115 fp=0x4210f48 runtime.main() /Users/bradfitz/go/src/pkg/runtime/proc.c:201 +0x113 fp=0x4210fa0 runtime.goexit() /Users/bradfitz/go/src/pkg/runtime/proc.c:1333 fp=0x4210fa8 exit status 2The text was updated successfully, but these errors were encountered: