On Aug 20, 2012, at 1:45 PM, Carl Sturtivant <[email protected]> wrote:
> I've been looking at the objects etcetera produced by dmd, and using D's > function demangle in std.demangle to decrypt some of the symbols found in > such objects by nm. > > http://sourceware.org/binutils/docs-2.22/binutils/nm.html > > While demangle does produce a demangled version of some symbols, it does not > in other cases where they nevertheless look as if they may be mangled names > of some kind. I considered that perhaps they are C++ mangled names, but have > been unable to get nm to unmangle them, even though it nominally knows about > C++ name mangling. > > Is there a better analog of demangle I can use to translate back some of > these more intractable mangled names? I tried the one in core.demangle but it > did no better. Or is there somewhere I could determine the demangling rules > and implement them for myself? Any suggestions will be gratefully received. std.demangle calls core.demangle, so it's no surprise that you got the same result. > Here are some examples that are not demangled by std.demangle.demangle : > > _D13libd_demangle12__ModuleInfoZ > _D15TypeInfo_Struct6__vtblZ > _D3std5stdio12__ModuleInfoZ > _D3std6traits15__T8DemangleTkZ8Demangle6__initZ > _D47TypeInfo_S3std6traits15__T8DemangleTkZ8Demangle6__initZ demangle is currently designed to demangle functions names, while the strings above are types. During parsing, demangle sees the string as a qualified name and then expects a type, and when it doesn't find one it figures the symbol isn't valid. It sounds like we either need a separate function for demangling types or if the demangle function encounters a 'Z' when it expects a type name it should realize it's demangling a type name, back up, and try again according to that logic. I suggest submitting a ticket. To learn how the demangler works, the easiest thing is to copy core.demangle into your workspace and compile a small app with it directly, turning on the debug info. For example: module abc; import demangle_; import std.stdio; void main() { writeln(decodeDmdString("_D47TypeInfo_S3std6traits15__T8DemangleTkZ8Demangle6__initZ")); } $ dmd abc -debug=trace -debug=info demangle
