Re: [PATCH 1/2] build: -no-pie is no functional linker flag

[Denis V. Lunev]

On 8/5/21 11:45 PM, Denis V. Lunev wrote:
> From: Christian Ehrhardt <christian.ehrhardt@canonical.com>
>
> Recent binutils changes dropping unsupported options [1] caused a build
> issue in regard to the optionroms.
>
>   ld -m elf_i386 -T /<<PKGBUILDDIR>>/pc-bios/optionrom//flat.lds -no-pie \
>     -s -o multiboot.img multiboot.o
>   ld.bfd: Error: unable to disambiguate: -no-pie (did you mean --no-pie ?)
>
> This isn't really a regression in ld.bfd, filing the bug upstream
> revealed that this never worked as a ld flag [2] - in fact it seems we
> were by accident setting --nmagic).
>
> Since it never had the wanted effect this usage of LDFLAGS_NOPIE, should be
> droppable without any effect. This also is the only use-case of LDFLAGS_NOPIE
> in .mak, therefore we can also remove it from being added there.
>
> [1]: https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=983d925d
> [2]: https://sourceware.org/bugzilla/show_bug.cgi?id=27050#c5
>
> Signed-off-by: Christian Ehrhardt <christian.ehrhardt@canonical.com>
> Message-Id: <20201214150938.1297512-1-christian.ehrhardt@canonical.com>
> Cc: qemu-stable@nongnu.org
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> ---
> Going to put this patch at the beginning of our branch. This fixes
> compilation on my Ubuntu 20.04.
>
>  configure                  | 3 ---
>  pc-bios/optionrom/Makefile | 1 -
>  2 files changed, 4 deletions(-)
>
> diff --git a/configure b/configure
> index b29aa04a6e..2c8384cb50 100755
> --- a/configure
> +++ b/configure
> @@ -2121,7 +2121,6 @@ EOF
>  # Check we support --no-pie first; we will need this for building ROMs.
>  if compile_prog "-Werror -fno-pie" "-no-pie"; then
>    CFLAGS_NOPIE="-fno-pie"
> -  LDFLAGS_NOPIE="-no-pie"
>  fi
>  
>  if test "$static" = "yes"; then
> @@ -2137,7 +2136,6 @@ if test "$static" = "yes"; then
>    fi
>  elif test "$pie" = "no"; then
>    CONFIGURE_CFLAGS="$CFLAGS_NOPIE $CONFIGURE_CFLAGS"
> -  CONFIGURE_LDFLAGS="$LDFLAGS_NOPIE $CONFIGURE_LDFLAGS"
>  elif compile_prog "-Werror -fPIE -DPIE" "-pie"; then
>    CONFIGURE_CFLAGS="-fPIE -DPIE $CONFIGURE_CFLAGS"
>    CONFIGURE_LDFLAGS="-pie $CONFIGURE_LDFLAGS"
> @@ -6756,7 +6754,6 @@ echo "QEMU_CXXFLAGS=$QEMU_CXXFLAGS" >> $config_host_mak
>  echo "GLIB_CFLAGS=$glib_cflags" >> $config_host_mak
>  echo "GLIB_LIBS=$glib_libs" >> $config_host_mak
>  echo "QEMU_LDFLAGS=$QEMU_LDFLAGS" >> $config_host_mak
> -echo "LDFLAGS_NOPIE=$LDFLAGS_NOPIE" >> $config_host_mak
>  echo "LD_I386_EMULATION=$ld_i386_emulation" >> $config_host_mak
>  echo "EXESUF=$EXESUF" >> $config_host_mak
>  echo "HOST_DSOSUF=$HOST_DSOSUF" >> $config_host_mak
> diff --git a/pc-bios/optionrom/Makefile b/pc-bios/optionrom/Makefile
> index 084fc10f05..30771f8d17 100644
> --- a/pc-bios/optionrom/Makefile
> +++ b/pc-bios/optionrom/Makefile
> @@ -41,7 +41,6 @@ override CFLAGS += $(call cc-option, $(Wa)-32)
>  
>  LD_I386_EMULATION ?= elf_i386
>  override LDFLAGS = -m $(LD_I386_EMULATION) -T $(SRC_DIR)/flat.lds
> -override LDFLAGS += $(LDFLAGS_NOPIE)
>  
>  all: multiboot.bin linuxboot.bin linuxboot_dma.bin kvmvapic.bin pvh.bin
>  
Guys,

I am sorry. Please disregard this letter. The patch was for
our downstream.

Den