template value parameter cause too long mangling

[dlangBugzillaToGithub]

Martin Nowak (@MartinNowak) reported this on 2013-10-13T13:39:20Z

Transferred from https://issues.dlang.org/show_bug.cgi?id=11248

CC List

• Walter Bright (@WalterBright)

Description

// huge tables
enum someData = [...];
enum someMoreData = [...];

template processData(alias data)
{
    // small result
    static immutable result = doSomething(data);
}

alias data = processData!someData;
alias moreData = processData!someMoreData;

----

The mangling becomes a problem because certain compile time data still ends up in the object file. When using the above pattern to process compile time data only the result should be part of the object file, but because the whole data is part of the template mangling we end up with a huge symbol name and a big object file.

I think a feasible solution is to abbreviate too long data in mangling by a hash (MD5 or SHA1).