Ping!
Regards
Senthil
On Mon, Nov 04, 2013 at 06:45:19PM +0530, Senthil Kumar Selvaraj wrote:
> The AVR backend does not generate position independent code, yet it
> happily accepts -fpic, -fPIC, -fpie and -fPIE. The generated code
> doesn't change at all. Also, it accepts the -shared option to generate a
> shared library, without really doing anything with it.
>
> This causes one of the regression tests
> (gcc.dg/lto/pr54709 c_lto_pr54709_0.o-c_lto_pr54709_1.o link) to fail with
> an 'undefined reference to main' error, when the test is trying to build
> a shared object.
>
> The attached patch generates a warning if one of the -f{pic,PIC,pie,PIE}
> options is provided, and an error if -shared is provided (
> config/mep/mep.c and config/s390/tpf.h already do something very similar).
>
> Regression tested with no new failures.Tests which exercise PIC now report as
> unsupported.
>
> If ok, could someone commit please? I don't have commit access.
>
> Regards
> Senthil
>
> gcc/ChangeLog
> 2013-11-04 Senthil Kumar Selvaraj <senthil_kumar.selva...@atmel.com>
>
> * config/avr/avr.c (avr_option_override): Warn if asked to generate
> position independent code.
> * config/avr/avr.h: Modify LINK_SPEC to reject -shared.
>
>
> diff --git gcc/config/avr/avr.c gcc/config/avr/avr.c
> index e7e1c2f..cf4b8ca 100644
> --- gcc/config/avr/avr.c
> +++ gcc/config/avr/avr.c
> @@ -310,6 +310,15 @@ avr_option_override (void)
> flag_omit_frame_pointer = 0;
> }
>
> + if (flag_pic == 1)
> + warning (OPT_fpic, "-fpic is not supported");
> + if (flag_pic == 2)
> + warning (OPT_fPIC, "-fPIC is not supported");
> + if (flag_pie == 1)
> + warning (OPT_fpie, "-fpie is not supported");
> + if (flag_pie == 2)
> + warning (OPT_fPIE, "-fPIE is not supported");
> +
> avr_current_device = &avr_mcu_types[avr_mcu_index];
> avr_current_arch = &avr_arch_types[avr_current_device->arch];
>
> diff --git gcc/config/avr/avr.h gcc/config/avr/avr.h
> index f223a61..1eff5be 100644
> --- gcc/config/avr/avr.h
> +++ gcc/config/avr/avr.h
> @@ -522,7 +522,8 @@ extern const char *avr_device_to_sp8 (int argc, const
> char **argv);
> mmcu=at90can64*|\
> mmcu=at90usb64*:--pmem-wrap-around=64k}}}\
> %:device_to_ld(%{mmcu=*:%*})\
> -%:device_to_data_start(%{mmcu=*:%*})"
> +%:device_to_data_start(%{mmcu=*:%*})\
> +%{shared:%eshared is not supported}"
>
> #define LIB_SPEC \
>
> "%{!mmcu=at90s1*:%{!mmcu=attiny11:%{!mmcu=attiny12:%{!mmcu=attiny15:%{!mmcu=attiny28:
> -lc }}}}}"
