From: Rafael Avila de Espindola <espindola@scylladb.com>
To: Thomas Monjalon <thomas@monjalon.net>
Cc: dev@dpdk.org
Subject: Re: [dpdk-dev] [PATCH] Don't combine '-r' and '--export-dynamic' linker options
Date: Thu, 12 Dec 2019 09:44:18 -0800 [thread overview]
Message-ID: <87a77xcubx.fsf@espindo.la> (raw)
In-Reply-To: <10040104.KzNOl4Vb3s@xps>
Thomas Monjalon <thomas@monjalon.net> writes:
> 25/10/2019 03:20, Rafael Ávila de Espíndola:
>> Running ld with '-r' switches the linker to a very special mode where
>> some other linker options don't make sense.
>>
>> In particular, '--export-dynamic' normally requires that all global
>> symbols be included in the dynamic symbol table, but a .o file doesn't
>> even have a dynamic symbol table.
>>
>> When given both options it looks like the gnu linker just ignores
>> '--export-dynamic'.
>>
>> Unfortunately some versions of lld (https://lld.llvm.org/) have a bug
>> that causes it to try to create a dynamic symbol table in the output
>> .o file and ends up corrupting it
>> (https://bugs.llvm.org/show_bug.cgi?id=43552). Current (git) version
>> of lld now issues an error.
>>
>> This patch drops $(LDFLAGS) when using -r. With this patch I can build
>> dpdk with lld.
> [...]
>> -PMDINFO_LD = $(CROSS)ld $(LDFLAGS) -r -o $@.o $@.pmd.o $@
>> +PMDINFO_LD = $(CROSS)ld -r -o $@.o $@.pmd.o $@
>
> Dealing with compiler bugs is really annoying.
> I'm afraid removing LDFLAGS may break in some environments.
> Could you just filter-out some incompatible options?
Sure, that works. I will send a v2.
> And what about meson? Is there some similar issue?
As far as I can tell meson produces a .a file instead. In the
build.ninja file I see
build drivers/librte_pmd_dpaa_event.a: STATIC_LINKER drivers/a715181@@rte_pmd_dpaa_event@sta/meson-generated_.._rte_pmd_dpaa_event.pmd.c.o drivers/a715181@@tmp_rte_pmd_dpaa_event@sta/event_dpaa_dpaa_eventdev.c.o
and
rule STATIC_LINKER
command = rm -f $out && gcc-ar $LINK_ARGS $out $in
Cheers,
Rafael
next prev parent reply other threads:[~2019-12-13 14:05 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-10-25 1:20 Rafael Ávila de Espíndola
2019-12-06 22:51 ` Rafael Avila de Espindola
2019-12-12 16:05 ` Thomas Monjalon
2019-12-12 17:44 ` Rafael Avila de Espindola [this message]
2019-12-13 10:07 ` Ray Kinsella
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