Re: [PATCH] Makerules: Remove no-op -Wl,-d when linking libc_pic.os

[Florian Weimer <fw@deneb.enyo.de>]

* Fangrui Song via Libc-alpha:

> In GNU ld, -d assigns space to common symbols for -r (i.e. change common
> symbols to STB_GLOBAL definitions).  This option was added in commit
> da2d1bc5adf49352232ad0514e79fbd5dcae08e8 (1998) likely because ld at
> that time had a bug that common symbols did not override shared object
> definitions.  -d has been long unneeded and more so since -fno-common
> was added to +cflags.
> ---
>  Makerules | 8 ++------
>  1 file changed, 2 insertions(+), 6 deletions(-)
>
> diff --git a/Makerules b/Makerules
> index dfe89e9e39..d1e139d03c 100644
> --- a/Makerules
> +++ b/Makerules
> @@ -633,14 +633,10 @@ LDFLAGS-c.so = -nostdlib -nostartfiles
>  LDLIBS-c.so += $(libc.so-gnulib)
>  # Give libc.so an entry point and make it directly runnable itself.
>  LDFLAGS-c.so += -e __libc_main
> -# Pre-link the objects of libc_pic.a so that we can locally resolve
> -# COMMON symbols before we link against ld.so.  This is because ld.so
> -# contains some of libc_pic.a already, which will prevent the COMMONs
> -# from being allocated in libc.so, which introduces evil dependencies
> -# between libc.so and ld.so, which can make it impossible to upgrade.
> +# Pre-link the objects of libc_pic.a for .gnu.glibc-stub.* processing.
>  $(common-objpfx)libc_pic.os: $(common-objpfx)libc_pic.a
>  	$(LINK.o) -nostdlib -nostartfiles -r -o $@ \
> -	$(LDFLAGS-c_pic.os) -Wl,-d $(whole-archive) $^ -o $@
> +	$(LDFLAGS-c_pic.os) $(whole-archive) $^ -o $@
>  
>  ifeq (,$(strip $(shlib-lds-flags)))
>  # Generate a list of -R options to excise .gnu.glibc-stub.* sections.

This looks okay to me, thanks.

Do you know what the .gnu.glibc-stub.* processing processing refers
to?