From e8de596f04d0ea7fb6fb68b036760bf088a9c6c2 Mon Sep 17 00:00:00 2001 From: Austin Clements Date: Fri, 20 Nov 2020 17:32:46 -0500 Subject: runtime: use inlined function name for traceback elision Currently, gentraceback decides which frames to print or elide when unwinding inlined frames using only the name of the outermost function. If the outermost function should be elided, then inlined functions will also be elided, even if they shouldn't be. This happens in practice in at least one situation. As of CL 258938, exported Go functions (and functions they call) can now be inlined into the generated _cgoexp_HASH_FN function. The runtime elides _cgoexp_HASH_FN from tracebacks because it doesn't contain a ".". Because of this bug, it also elides anything that was inlined into it. This CL fixes this by synthesizing a funcInfo for the inlined functions to pass to showframe. Fixes #42754. Change-Id: Ie6c663a4a1ac7f0d4beb1aa60bc26fc8cddd0f9d Reviewed-on: https://go-review.googlesource.com/c/go/+/272131 Trust: Austin Clements Run-TryBot: Austin Clements TryBot-Result: Go Bot Reviewed-by: Cherry Zhang --- src/runtime/traceback.go | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) (limited to 'src/runtime/traceback.go') diff --git a/src/runtime/traceback.go b/src/runtime/traceback.go index f3df152535..0825e9e707 100644 --- a/src/runtime/traceback.go +++ b/src/runtime/traceback.go @@ -396,13 +396,21 @@ func gentraceback(pc0, sp0, lr0 uintptr, gp *g, skip int, pcbuf *uintptr, max in // If there is inlining info, print the inner frames. if inldata := funcdata(f, _FUNCDATA_InlTree); inldata != nil { inltree := (*[1 << 20]inlinedCall)(inldata) + var inlFunc _func + inlFuncInfo := funcInfo{&inlFunc, f.datap} for { ix := pcdatavalue(f, _PCDATA_InlTreeIndex, tracepc, nil) if ix < 0 { break } - if (flags&_TraceRuntimeFrames) != 0 || showframe(f, gp, nprint == 0, inltree[ix].funcID, lastFuncID) { - name := funcnameFromNameoff(f, inltree[ix].func_) + + // Create a fake _func for the + // inlined function. + inlFunc.nameoff = inltree[ix].func_ + inlFunc.funcID = inltree[ix].funcID + + if (flags&_TraceRuntimeFrames) != 0 || showframe(inlFuncInfo, gp, nprint == 0, inlFuncInfo.funcID, lastFuncID) { + name := funcname(inlFuncInfo) file, line := funcline(f, tracepc) print(name, "(...)\n") print("\t", file, ":", line, "\n") @@ -811,6 +819,9 @@ func showframe(f funcInfo, gp *g, firstFrame bool, funcID, childID funcID) bool // showfuncinfo reports whether a function with the given characteristics should // be printed during a traceback. func showfuncinfo(f funcInfo, firstFrame bool, funcID, childID funcID) bool { + // Note that f may be a synthesized funcInfo for an inlined + // function, in which case only nameoff and funcID are set. + level, _, _ := gotraceback() if level > 1 { // Show all frames. -- cgit v1.3-5-g9baa