Re: [PATCH v2] Xen: Update compiler checks

[Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>]

On 3/27/25 5:31 PM, Andrew Cooper wrote:

> We have checks in both xen/compiler.h, and Config.mk.  Both are incomplete.
> Remove the one from compiler.h, as it's pointless to perform in addition to
> the xen.git-wide one as well.
>
> Expand the checks to cover RISCV wanting GCC 11.1, and to cover Clang on x86.
>     
Why GCC 11.1 for RISC-V? We declared in ./README that 12.2.

~ Oleksii
> PPC still is unspecified, and inherits the GCC 5.1 global baseline.
>
> Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
> ---
> CC: Anthony PERARD <anthony.perard@xxxxxxxxxx>
> CC: Michal Orzel <michal.orzel@xxxxxxx>
> CC: Jan Beulich <jbeulich@xxxxxxxx>
> CC: Julien Grall <julien@xxxxxxx>
> CC: Roger Pau Monné <roger.pau@xxxxxxxxxx>
> CC: Stefano Stabellini <sstabellini@xxxxxxxxxx>
> CC: Oleksii Kurochko <oleksii.kurochko@xxxxxxxxx>
>
> v2:
>  * Change to altering Config.mk
>
> https://gitlab.com/xen-project/people/andyhhp/xen/-/pipelines/1738628602 with
> the CI changes reverted, so as to expect failures for CentOS 7 and earlier
> Ubuntu Clangs.
>
> The $(eval $(check-y)) is badly positioned:
>
>   xen.git/xen$ make
>   *** FATAL BUILD ERROR: Xen requires at least GCC 0x150100
>   *** FATAL BUILD ERROR: Xen requires at least GCC 0x150100
>   *** FATAL BUILD ERROR: Xen requires at least GCC 0x150100
>   *** FATAL BUILD ERROR: Xen requires at least GCC 0x150100
>   *** FATAL BUILD ERROR: Xen requires at least GCC 0x150100
>   *** FATAL BUILD ERROR: Xen requires at least GCC 0x150100
>   *** FATAL BUILD ERROR: Xen requires at least GCC 0x150100
>   *** FATAL BUILD ERROR: Xen requires at least GCC 0x150100
>   *** FATAL BUILD ERROR: Xen requires at least GCC 0x150100
>   *** FATAL BUILD ERROR: Xen requires at least GCC 0x150100
>   *** FATAL BUILD ERROR: Xen requires at least GCC 0x150100
>   *** FATAL BUILD ERROR: Xen requires at least GCC 0x150100
>   *** FATAL BUILD ERROR: Xen requires at least GCC 0x150100
>   *** FATAL BUILD ERROR: Xen requires at least GCC 0x150100
>   *** FATAL BUILD ERROR: Xen requires at least GCC 0x150100
>     HOSTCC  tools/fixdep
>   *** FATAL BUILD ERROR: Xen requires at least GCC 0x150100
>   make[1]: *** [scripts/Makefile.host:108: tools/fixdep] Error 1
>     HOSTCC  tools/symbols
>   *** FATAL BUILD ERROR: Xen requires at least GCC 0x150100
>   make[1]: *** [scripts/Makefile.host:108: tools/symbols] Error 1
>   make: *** [Makefile:610: xen] Error 2
>
> It is involved every time Config.mk is included, rather than once per `make`
> invocation.
> ---
>  Config.mk                  | 14 ++++++++++++--
>  xen/include/xen/compiler.h | 14 --------------
>  2 files changed, 12 insertions(+), 16 deletions(-)
>
> diff --git a/Config.mk b/Config.mk
> index 8a73f3da62b4..a9d62fc10cfa 100644
> --- a/Config.mk
> +++ b/Config.mk
> @@ -125,8 +125,18 @@ define cc-ver-check-closure
>      endif
>  endef
>  
> -# Require GCC v4.1+
> -check-$(gcc) = $(call cc-ver-check,CC,0x040100,"Xen requires at least gcc-4.1")
> +# Minimum GCC version: 5.1, except for RISCV which needs 11.1
> +ifeq ($(XEN_TARGET_ARCH),riscv64)
> +check-$(gcc) = $(call cc-ver-check,CC,0x110100,"Xen requires at least GCC 11.1")
> +else
> +check-$(gcc) = $(call cc-ver-check,CC,0x050100,"Xen requires at least GCC 5.1")
> +endif
> +
> +# Minimum Clang version: 11, x86 only
> +ifeq ($(XEN_TARGET_ARCH),x86_64)
> +check-$(clang) = $(call cc-ver-check,CC,0x110000,"Xen requires at least Clang 11")
> +endif
> +
>  $(eval $(check-y))
>  
>  ld-ver-build-id = $(shell $(1) --build-id 2>&1 | \
> diff --git a/xen/include/xen/compiler.h b/xen/include/xen/compiler.h
> index 636a85bc417d..43b666133a92 100644
> --- a/xen/include/xen/compiler.h
> +++ b/xen/include/xen/compiler.h
> @@ -1,20 +1,6 @@
>  #ifndef __LINUX_COMPILER_H
>  #define __LINUX_COMPILER_H
>  
> -#if !defined(__GNUC__) || (__GNUC__ < 4)
> -#error Sorry, your compiler is too old/not recognized.
> -#elif CONFIG_CC_IS_GCC
> -# if defined(CONFIG_ARM_32) && CONFIG_GCC_VERSION < 40900
> -#  error Sorry, your version of GCC is too old - please use 4.9 or newer.
> -# elif defined(CONFIG_ARM_64) && CONFIG_GCC_VERSION < 50100
> -/*
> - * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63293
> - * https://lore.kernel.org/r/20210107111841.GN1551@xxxxxxxxxxxxxxxxxxxxx
> - */
> -#  error Sorry, your version of GCC is too old - please use 5.1 or newer.
> -# endif
> -#endif
> -
>  #ifdef CONFIG_CC_HAS_VISIBILITY_ATTRIBUTE
>  /* Results in more efficient PIC code (no indirections through GOT or PLT). */
>  #pragma GCC visibility push(hidden)
>