Re: [PATCH v3 3/4] Remove --with-default-link configure option

[Carlos O'Donell <carlos@redhat.com>]

On 12/27/22 16:11, Adhemerval Zanella via Libc-alpha wrote:
> Now that there is no need to use a special linker script to hardening

s/hardening/harden/g

> internal data structures, remove the --with-default-link configure
> option and associated definitions.

LGTM.

Please post v4.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>

> ---
>  INSTALL                   |  6 ------
>  Makerules                 | 21 ++++++---------------
>  config.make.in            |  1 -
>  configure                 | 13 -------------
>  configure.ac              |  7 -------
>  elf/Makefile              |  2 --
>  iconvdata/extra-module.mk |  2 +-
>  manual/install.texi       |  6 ------
>  8 files changed, 7 insertions(+), 51 deletions(-)
> 
> diff --git a/INSTALL b/INSTALL
> index 659f75a97f..f57c743d77 100644
> --- a/INSTALL
> +++ b/INSTALL
> @@ -90,12 +90,6 @@ if 'CFLAGS' is specified it must enable optimization.  For example:
>       library will still be usable, but functionality may be lost--for
>       example, you can't build a shared libc with old binutils.
>  
> -'--with-default-link'
> -     With '--with-default-link', the build system does not use a custom
> -     linker script for linking shared objects.  The default is
> -     '--without-default-link', because the custom linker script is
> -     needed for full RELRO protection.
> -

OK.

>  '--with-nonshared-cflags=CFLAGS'
>       Use additional compiler flags CFLAGS to build the parts of the
>       library which are always statically linked into applications and
> diff --git a/Makerules b/Makerules
> index 41fc8db4ba..97864402fb 100644
> --- a/Makerules
> +++ b/Makerules
> @@ -544,13 +544,8 @@ $(LINK.o) -shared -static-libgcc -Wl,-O1 $(sysdep-LDFLAGS) \
>  	  -L$(subst :, -L,$(rpath-link)) -Wl,-rpath-link=$(rpath-link)
>  endef
>  
> -# If the linker is good enough, we can let it use its default linker script.
> -# In the long term the custom linker script will be removed.
> -shlib-lds =
> -shlib-lds-flags =
> -

OK.

>  define build-shlib
> -$(build-shlib-helper) -o $@ $(shlib-lds-flags) \
> +$(build-shlib-helper) -o $@ \

OK.

>  	  $(csu-objpfx)abi-note.o $(build-shlib-objlist)
>  endef
>  
> @@ -569,12 +564,12 @@ endef
>  # binutils only position loadable notes into the first page for binaries,
>  # not for shared objects
>  define build-module
> -$(build-module-helper) -o $@ $(shlib-lds-flags) \
> +$(build-module-helper) -o $@ \
>  	  $(csu-objpfx)abi-note.o $(build-module-objlist) $(link-libc-args)
>  $(call after-link,$@)
>  endef
>  define build-module-asneeded
> -$(build-module-helper) -o $@ $(shlib-lds-flags) \
> +$(build-module-helper) -o $@ \
>  	  $(csu-objpfx)abi-note.o \
>  	  -Wl,--as-needed $(build-module-objlist) -Wl,--no-as-needed \
>  	  $(link-libc-args)
> @@ -606,7 +601,6 @@ $(common-objpfx)libc_pic.os: $(common-objpfx)libc_pic.a
>  	$(LINK.o) -nostdlib -nostartfiles -r -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.
>  $(common-objpfx)libc_pic.opts: $(common-objpfx)libc_pic.os
>  	$(OBJDUMP) -h $< | \
> @@ -620,7 +614,6 @@ $(common-objpfx)libc_pic.os.clean: $(common-objpfx)libc_pic.opts \
>  generated += libc_pic.opts libc_pic.os.clean
>  
>  libc_pic_clean := .clean
> -endif

OK.

>  
>  # Build a possibly-modified version of libc_pic.a for use in building
>  # linkobj/libc.so.
> @@ -650,16 +643,14 @@ $(common-objpfx)linkobj/libc.so: link-libc-deps = # empty
>  $(common-objpfx)libc.so: $(common-objpfx)libc_pic.os$(libc_pic_clean) \
>  			 $(elf-objpfx)sofini.os \
>  			 $(elf-objpfx)interp.os \
> -			 $(elf-objpfx)ld.so \
> -			 $(shlib-lds)
> +			 $(elf-objpfx)ld.so
>  	$(build-shlib)
>  	$(call after-link,$@)
>  
>  $(common-objpfx)linkobj/libc.so: $(common-objpfx)linkobj/libc_pic.a \
>  			 $(elf-objpfx)sofini.os \
>  			 $(elf-objpfx)interp.os \
> -			 $(elf-objpfx)ld.so \
> -			 $(shlib-lds)
> +			 $(elf-objpfx)ld.so
>  	$(build-shlib)
>  	$(call after-link,$@)
>  
> @@ -720,7 +711,7 @@ endif
>  
>  extra-modules-build := $(filter-out $(modules-names-nobuild),$(modules-names))
>  $(extra-modules-build:%=$(objpfx)%.so): $(objpfx)%.so: \
> -		$(objpfx)%.os $(shlib-lds) $(link-libs-deps)
> +		$(objpfx)%.os $(link-libs-deps)
>  	$(build-module)
>  endif
>  \f
> diff --git a/config.make.in b/config.make.in
> index d7c416cbea..befcc22625 100644
> --- a/config.make.in
> +++ b/config.make.in
> @@ -69,7 +69,6 @@ have-libaudit = @have_libaudit@
>  have-libcap = @have_libcap@
>  have-cc-with-libunwind = @libc_cv_cc_with_libunwind@
>  bind-now = @bindnow@
> -use-default-link = @use_default_link@

OK.

>  have-cxx-thread_local = @libc_cv_cxx_thread_local@
>  have-loop-to-function = @libc_cv_cc_loop_to_function@
>  have-textrel_ifunc = @libc_cv_textrel_ifunc@
> diff --git a/configure b/configure
> index 62c2581cb0..df2e126e6f 100755
> --- a/configure
> +++ b/configure
> @@ -678,7 +678,6 @@ hardcoded_path_in_tests
>  enable_timezone_tools
>  rtld_early_cflags
>  extra_nonshared_cflags
> -use_default_link
>  sysheaders
>  ac_ct_CXX
>  CXXFLAGS
> @@ -756,7 +755,6 @@ with_gd_lib
>  with_binutils
>  with_selinux
>  with_headers
> -with_default_link
>  with_nonshared_cflags
>  with_rtld_early_cflags
>  with_timeoutfactor
> @@ -1475,7 +1473,6 @@ Optional Packages:
>    --with-selinux          if building with SELinux support
>    --with-headers=PATH     location of system headers to use (for example
>                            /usr/src/linux/include) [default=compiler default]
> -  --with-default-link     do not use explicit linker scripts

OK.

>    --with-nonshared-cflags=CFLAGS
>                            build nonshared libraries with additional CFLAGS
>    --with-rtld-early-cflags=CFLAGS
> @@ -3459,16 +3456,6 @@ fi
>  
>  
>  
> -
> -# Check whether --with-default-link was given.
> -if test "${with_default_link+set}" = set; then :
> -  withval=$with_default_link; use_default_link=$withval
> -else
> -  use_default_link=no
> -fi
> -
> -
> -

OK.

>  # Check whether --with-nonshared-cflags was given.
>  if test "${with_nonshared_cflags+set}" = set; then :
>    withval=$with_nonshared_cflags; extra_nonshared_cflags=$withval
> diff --git a/configure.ac b/configure.ac
> index 022b8f68bc..a57303938e 100644
> --- a/configure.ac
> +++ b/configure.ac
> @@ -149,13 +149,6 @@ AC_ARG_WITH([headers],
>  	    [sysheaders=''])
>  AC_SUBST(sysheaders)
>  
> -AC_SUBST(use_default_link)
> -AC_ARG_WITH([default-link],
> -	    AS_HELP_STRING([--with-default-link],
> -			   [do not use explicit linker scripts]),
> -	    [use_default_link=$withval],
> -	    [use_default_link=no])
> -

OK.

>  dnl Additional build flags injection.
>  AC_ARG_WITH([nonshared-cflags],
>  	    AS_HELP_STRING([--with-nonshared-cflags=CFLAGS],
> diff --git a/elf/Makefile b/elf/Makefile
> index f5157030c4..05f9b6dd54 100644
> --- a/elf/Makefile
> +++ b/elf/Makefile
> @@ -1233,8 +1233,6 @@ endif
>  # Command to link into a larger single relocatable object.
>  reloc-link = $(LINK.o) -nostdlib -nostartfiles -r
>  
> -$(objpfx)sotruss-lib.so: $(shlib-lds)
> -

OK.

>  $(objpfx)dl-allobjs.os: $(all-rtld-routines:%=$(objpfx)%.os)
>  	$(reloc-link) -o $@ $^
>  
> diff --git a/iconvdata/extra-module.mk b/iconvdata/extra-module.mk
> index ecaf507624..a816659763 100644
> --- a/iconvdata/extra-module.mk
> +++ b/iconvdata/extra-module.mk
> @@ -4,7 +4,7 @@ extra-modules-left := $(strip $(filter-out $(mod),$(extra-modules-left)))
>  extra-objs := $(extra-objs) $(patsubst %,%.os,$($(mod)-routines))
>  
>  $(objpfx)$(mod).so: $(addprefix $(objpfx),$(addsuffix .os,$($(mod)-routines)))\
> -		    $(shlib-lds) $(link-libc-deps)
> +		    $(link-libc-deps)
>  	$(build-module-asneeded)
>  
>  ifneq (,$(extra-modules-left))
> diff --git a/manual/install.texi b/manual/install.texi
> index c775005581..ba2231024b 100644
> --- a/manual/install.texi
> +++ b/manual/install.texi
> @@ -117,12 +117,6 @@ problem and suppress these constructs, so that the library will still be
>  usable, but functionality may be lost---for example, you can't build a
>  shared libc with old binutils.
>  
> -@item --with-default-link
> -With @code{--with-default-link}, the build system does not use a custom
> -linker script for linking shared objects.  The default is
> -@code{--without-default-link}, because the custom linker script is
> -needed for full RELRO protection.
> -
>  @item --with-nonshared-cflags=@var{cflags}
>  Use additional compiler flags @var{cflags} to build the parts of the
>  library which are always statically linked into applications and

OK.

-- 
Cheers,
Carlos.