A simple question

[Adam D. Ruppe]

On Friday, 16 November 2012 at 00:29:24 UTC, David Nadlinger 
wrote:
> Granted, the diagnostics for it are terrible, you just get to 
> see the raw linker error message.

This is potentially very easy to fix...

$ cat demangle.d
import core.demangle;
import std.stdio;
import std.regex;

string dem(Captures!(char[], uint) m) {
         return demangle(m.hit).idup;
}

void main(string[] args) {
         if(args.length > 1) {
                 foreach(arg; args[1..$])
                         writeln(demangle(arg));
                 return;
         }

         foreach(line; stdin.byLine) {
                 writeln(line.replace!dem(regex("_D[a-zA-Z0-9_]+", 
"g")));
         }
}

$ cat /home/me/demangle_gcc
#!/bin/bash

exec gcc $* 2>&1 | /home/me/demangle

$ export CC=/home/me/demangle_gcc

$ dmd test2.d
test2.o: In function `_Dmain':
test2.d:(.text._Dmain+0x34): undefined reference to 
`_D9something1A7__ClassZ'
test2.d:(.text._Dmain+0x41): undefined reference to `something.A 
something.A.__ctor(int)'
collect2: ld returned 1 exit status


A little more readable than 
`_D9something1A6__ctorMFiZC9something1A'!


core.demangle apparently has some bugs, but these simple little 
scripts help to beautify the linker output without actually 
changing anything.

On Windows, the environment variable LINKCMD is used instead of 
CC. Other than that and other little details, I'm sure the same 
approach would work.


Now, append "CC=/home/me/demangle_gcc" to your dmd.conf... and 
there's now no need to set the environment variable in your shell.


So if we made those demangle scripts and put them in the zip with 
dmd, then changed dmd.conf to use the helper script 
(CC=%@P%demangle_gcc on linux, LINKCMD=demangle_link.bat on 
windows).... and there you go, demangled linker output.

A fancier script could detect things like ModuleInfo and give a 
helpful hint afterwards.