SIGSEGV on OSX when compiling

[ghostwheel]

When lit is compiling as well as weaving, I get SIGSEGV.
Top of my file is:

@code_type c++ .cpp
@comment_type // %s
@Compiler lit -t main3.lit && g++ -c main3.cpp

It has compile errors. When I run lit -c, I get

'lit -c main3.lit' terminated by signal SIGSEGV (Address boundary error)

I think this is because the compiler outputs lines that lit can not process.
This is in main.lit:

        auto matches = matchFirst(line, r);

        string linenum = matches["linenum"];
        string fname = matches["filename"];
        string message = matches["message"];

I think one needs to first check if matches is empty. For example, if I condition the rest with

if( !matches.empty ) {

I don't get SIGSEGV, lit exits normally. I'm not sure if the best is if or assert.

I thought D won't have these annoying SIGSEGV!