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Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <4da71cb981057048e8cf9dec8731ad936b433e38.1611155254.git.szabolcs.nagy@arm.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Adhemerval Zanella via Libc-alpha Reply-To: Adhemerval Zanella Errors-To: libc-alpha-bounces@sourceware.org Sender: "Libc-alpha" On 20/01/2021 12:31, Szabolcs Nagy via Libc-alpha wrote: > All linkers support __ehdr_start that support static PIE linking, > so there is no need to check for its presence via a weak reference. > > This avoids a RELATIVE relocation in static PIE startup code on some > targets. > > With non-PIE static linking the weak ref check is kept in case the > linker does not support __ehdr_start. LGTM, thanks. Reviewed-by: Adhemerval Zanella > --- > csu/libc-start.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/csu/libc-start.c b/csu/libc-start.c > index db859c3bed..5b9ce1d158 100644 > --- a/csu/libc-start.c > +++ b/csu/libc-start.c > @@ -175,8 +175,12 @@ LIBC_START_MAIN (int (*main) (int, char **, char ** MAIN_AUXVEC_DECL), > information from auxv. */ > > extern const ElfW(Ehdr) __ehdr_start > +# if BUILD_PIE_DEFAULT > + __attribute__ ((visibility ("hidden"))); > +# else > __attribute__ ((weak, visibility ("hidden"))); > if (&__ehdr_start != NULL) > +# endif > { > assert (__ehdr_start.e_phentsize == sizeof *GL(dl_phdr)); > GL(dl_phdr) = (const void *) &__ehdr_start + __ehdr_start.e_phoff; >