cmd/link/internal/ld: panic if inlined functions missing FuncInfo

All inlined functions are Go functions, and thus should be capable of
having a FuncInfo. Missing FuncInfo is likely indication of a compiler
bug that dropped the symbol too early, failing to add it to the symbol
list used for writing output. I believe all existing cases have been
fixed; this check will prevent regressions.

The exception is -linkshared mode. There symbols are loaded from the
shared library, and the FuncInfo is not available. This is a bug, as it
can result in incorrect the FuncID in inlinedCall, but it is very
involved to fix.

For #54959.
For #55954.

Change-Id: Ib0dc4f1ea62525b55f68604d6013ff33223fdcdd
Reviewed-on: https://go-review.googlesource.com/c/go/+/429637
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Michael Pratt <mpratt@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
This commit is contained in:
Michael Pratt 2022-09-09 12:29:48 -04:00
parent 33738ddd0a
commit 8a0cf719a6

View file

@ -171,7 +171,18 @@ func genInlTreeSym(ctxt *Link, cu *sym.CompilationUnit, fi loader.FuncInfo, arch
var funcID objabi.FuncID
if inlFunc.Valid() {
funcID = inlFunc.FuncID()
} else if !ctxt.linkShared {
// Inlined functions are always Go functions, and thus
// must have FuncInfo.
//
// Unfortunately, with -linkshared, the inlined
// function may be external symbols (from another
// shared library), and we don't load FuncInfo from the
// shared library. We will report potentially incorrect
// FuncID in this case. See https://go.dev/issue/55954.
panic(fmt.Sprintf("inlined function %s missing func info", ldr.SymName(call.Func)))
}
// Construct runtime.inlinedCall value.
const size = 12
inlTreeSym.SetUint8(arch, int64(i*size+0), uint8(funcID))