Re: musl-llvm and crtbegin/crtend

["writeonce@midipix.org" <writeonce@midipix.org>]

On 04/23/2014 10:47 AM, Rich Felker wrote:
> On Wed, Apr 23, 2014 at 04:47:55AM -0400, writeonce@midipix.org wrote:
>> Thanks, Rich.  From the sources of gcc (4.6 -- 4.8) and llvm/clang
>> (3.4 -- trunk) it appears that gcc introduced __init_array in
>> version 4.7;  when used, __do_global_ctors_aux is absent, however
>> the implementation of __do_global_dtors_aux is still there (in
>> crtbegin.o).
>>
>> When clang invokes the linker, it asks for crtbegin.o and crtend.o
>> to be included regardless of the executable type (c/c++), which
>> might be worth a patch (clang/lib/Driver/Tools.cpp).  On the other
>> hand, it does support __init_array (by default, I believe, and also
>> through -fuse-init-array), and there are also relevant bits in the
>> code for llvm's native linker (lld).
>>
>> Given that clang also supports the old ctor/dtor system (through
>> -fno-use-init-array), the status of crtbegin/crtend seems to be
>> still relevant.
> My point was just that if you're using exclusively new .o files built
> with init-array, I think it's possible to compile without crtbegin.o
> and crtend.o (or equivalently, with empty .o files dropped in their
> place).
>
> Rich
>
>
Thanks for clarifying this, I'll test this with both systems (gcc & 
llvm) and get back to the list.
zg