[Buildroot] [PATCH 1/1] package/capnproto: update ucontext handling

[Arnout Vandecappelle]

On 06/03/2024 15:55, Fabrice Fontaine wrote:
> musl workaround for getcontext/setcontext is not needed since commit
> eaeba56aa2d21f1d264c7e361731808e3f072d9d
> 
> Moreover, select libucontext if possible to get full ucontext support
> 
> Signed-off-by: Fabrice Fontaine <fontaine.fabrice at gmail.com>
> ---
>   package/c-capnproto/Config.in  | 6 ++++--
>   package/capnproto/Config.in    | 8 ++++++--
>   package/capnproto/capnproto.mk | 5 ++---
>   3 files changed, 12 insertions(+), 7 deletions(-)
> 
> diff --git a/package/c-capnproto/Config.in b/package/c-capnproto/Config.in
> index c472128c3f..abe2a602ba 100644
> --- a/package/c-capnproto/Config.in
> +++ b/package/c-capnproto/Config.in
> @@ -7,7 +7,8 @@ config BR2_PACKAGE_C_CAPNPROTO
>   	depends on BR2_TOOLCHAIN_HAS_THREADS # capnproto
>   	depends on BR2_TOOLCHAIN_HAS_ATOMIC # capnproto
>   	depends on !BR2_TOOLCHAIN_HAS_GCC_BUG_64735 # capnproto
> -	depends on BR2_TOOLCHAIN_HAS_UCONTEXT # capnproto
> +	depends on BR2_TOOLCHAIN_HAS_UCONTEXT || \
> +		BR2_PACKAGE_LIBUCONTEXT_ARCH_SUPPORTS # capnproto
>   	select BR2_PACKAGE_CAPNPROTO
>   	help
>   	  A C plugin for Cap'n Proto. Generates the code generator
> @@ -24,4 +25,5 @@ comment "c-capnproto needs host and target gcc >= 5 w/ C++14, threads, atomic, u
>   		!BR2_TOOLCHAIN_HAS_THREADS || \
>   		!BR2_TOOLCHAIN_HAS_ATOMIC || \
>   		BR2_TOOLCHAIN_HAS_GCC_BUG_64735 || \
> -		!BR2_TOOLCHAIN_HAS_UCONTEXT
> +		!(BR2_TOOLCHAIN_HAS_UCONTEXT || \
> +			BR2_PACKAGE_LIBUCONTEXT_ARCH_SUPPORTS)
> diff --git a/package/capnproto/Config.in b/package/capnproto/Config.in
> index 943ba9de29..93e3a64fb8 100644
> --- a/package/capnproto/Config.in
> +++ b/package/capnproto/Config.in
> @@ -7,7 +7,10 @@ config BR2_PACKAGE_CAPNPROTO
>   	depends on BR2_TOOLCHAIN_HAS_THREADS
>   	depends on BR2_TOOLCHAIN_HAS_ATOMIC
>   	depends on !BR2_TOOLCHAIN_HAS_GCC_BUG_64735
> -	depends on BR2_TOOLCHAIN_HAS_UCONTEXT
> +	depends on BR2_TOOLCHAIN_HAS_UCONTEXT || \
> +		BR2_PACKAGE_LIBUCONTEXT_ARCH_SUPPORTS
> +	select BR2_PACKAGE_LIBUCONTEXT if \
> +		BR2_PACKAGE_LIBUCONTEXT_ARCH_SUPPORTS

  This will select libucontext even if the toolchain already has ucontext, so we 
have it twice? Is that really OK, and even if it is, is it really what we want? 
My feeling is that libucontext should depend on !BR2_TOOLCHAIN_HAS_UCONTEXT...
And here, I feel it should be "if !BR2_TOOLCHAIN_HAS_UCONTEXT && 
BR2_PACKAGE_LIBUCONTEXT_ARCH_SUPPORTS". Which is a bit too cumbersome to repeat 
in many places, so maybe we should also introduce an auxiliary symbol for that, 
something like BR2_PACKAGE_LIBUCONTEXT_IF_NEEDED.


  Regards,
  Arnout

>   	help
>   	  Cap'n Proto is an insanely fast data interchange format
>   	  and capability-based RPC system. Think JSON, except
> @@ -25,4 +28,5 @@ comment "capnproto needs host and target gcc >= 5 w/ C++14, threads, atomic, uco
>   		!BR2_TOOLCHAIN_HAS_THREADS || \
>   		!BR2_TOOLCHAIN_HAS_ATOMIC || \
>   		BR2_TOOLCHAIN_HAS_GCC_BUG_64735 || \
> -		!BR2_TOOLCHAIN_HAS_UCONTEXT
> +		!(BR2_TOOLCHAIN_HAS_UCONTEXT || \
> +			BR2_PACKAGE_LIBUCONTEXT_ARCH_SUPPORTS)
> diff --git a/package/capnproto/capnproto.mk b/package/capnproto/capnproto.mk
> index 7424a1420f..d322c27a54 100644
> --- a/package/capnproto/capnproto.mk
> +++ b/package/capnproto/capnproto.mk
> @@ -29,9 +29,8 @@ else
>   CAPNPROTO_CONF_OPTS += --without-openssl
>   endif
>   
> -# musl doesn't support getcontext/setcontext
> -ifeq ($(BR2_TOOLCHAIN_USES_MUSL),y)
> -CAPNPROTO_CONF_ENV += CXXFLAGS="$(TARGET_CXXFLAGS) -DKJ_USE_FIBERS=0"
> +ifeq ($(BR2_PACKAGE_LIBUCONTEXT),y)
> +CAPNPROTO_DEPENDENCIES += libucontext
>   endif
>   
>   $(eval $(autotools-package))