there may be an omission of pcdata handling

[fumeboy]

compare 2 code snippet below:

// goloader/ld.go
	for _, pcdata := range symbol.Func.PCData {
		Func.PCData = append(Func.PCData, uint32(len(linker.pclntable)))
		linker.pclntable = append(linker.pclntable, pcdata...)
	}

// GoSDK(1.19.6)/cmd/link/internal/ld/pcln.go
	saveOffset := func(pcSym loader.Sym) {
		if _, ok := seen[pcSym]; !ok {
			datSize := ldr.SymSize(pcSym)
			if datSize != 0 {
				ldr.SetSymValue(pcSym, size)
			} else {
				// Invalid PC data, record as zero.
				ldr.SetSymValue(pcSym, 0)
			}
			size += datSize
			seen[pcSym] = struct{}{}
		}
	}

and the diff is goloader have not handle the case of datSize == 0, i think the right solution should be this:

	for _, pcdata := range symbol.Func.PCData {
		if len(pcdata) == 0 { append( ,0); continue }
		Func.PCData = append(Func.PCData, uint32(len(linker.pclntable)))
		linker.pclntable = append(linker.pclntable, pcdata...)
	}

[fumeboy]

if the compiler disable inline, funcinfo may have an PCDATA[2] InlTreeIndex with empty data.

i found this by reviewing go source code, and the runtime haven’t encountered some error in my executions.

[pkujhd]

@fumeboy , it is a bug, if a PCData is empty data, pcdata offset needs zero.
you haven't encountered some error because golang runtime checks funcdata before get pcdata.