Re: [dpdk-dev] [PATCH] build: fix soname for experimental libraries

[Bruce Richardson <bruce.richardson@intel.com>]

On Tue, Feb 18, 2020 at 12:44:02AM +0100, Thomas Monjalon wrote:
> Because of an original mistake in ABI numbering,
> and a temporary workaround for ABI 20,
> for experimental libs, numbering would lead to consider
> 	ABI 20.1 > ABI 21.0
> 
> Before this patch:
> 
> DPDK 19.11: ABI version 0.200 and soname 0.20
> DPDK 20.02: ABI version 0.2001 and soname 0.201
> Numbers are increasing, that's fine.
> For the next major ABI, back to normal numbering:
> DPDK 20.11: ABI version 0.210 and soname 0.21
> Numbers are decreasing!
> 
> After this patch:
> 
> DPDK 19.11: ABI version 0.200 and soname 0.20
> DPDK 20.02: ABI version 0.201 and soname 0.20
> DPDK 20.11: ABI version 0.210 and soname 0.21
> 
> Fixes: f26c2b39b271 ("build: fix soname info for 19.11 compatibility")
> 
> Signed-off-by: Thomas Monjalon <thomas@monjalon.net>
> ---
>  config/meson.build | 8 ++++----
>  mk/rte.lib.mk      | 4 ++--
>  2 files changed, 6 insertions(+), 6 deletions(-)
> 
> diff --git a/config/meson.build b/config/meson.build
> index 6c46767e3e..e7cd74e2c2 100644
> --- a/config/meson.build
> +++ b/config/meson.build
> @@ -27,12 +27,12 @@ abi_version = run_command(find_program('cat', 'more'),
>  # and the filename suffix as 0.majorminor versions,
>  # e.g. v20.1 => librte_stable.so.20.1, librte_experimental.so.0.201
>  #    sonames => librte_stable.so.20, librte_experimental.so.0.20
> -# e.g. v20.0.1 => librte_stable.so.20.0.1, librte_experimental.so.0.2001
> -#      sonames => librte_stable.so.20.0, librte_experimental.so.0.200
> +# e.g. v20.0.1 => librte_stable.so.20.0.1, librte_experimental.so.0.201
> +#      sonames => librte_stable.so.20.0, librte_experimental.so.0.20
>  abi_va = abi_version.split('.')
>  stable_so_version = abi_va.length() == 2 ? abi_va[0] : abi_va[0] + '.' + abi_va[1]
> -experimental_abi_version = '0.' + ''.join(abi_va)
> -experimental_so_version = '0.' + ''.join(stable_so_version.split('.'))
> +experimental_abi_version = '0.' + ''.join([abi_va[0], abi_va[2]])
> +experimental_so_version = '0.' + ''.join([abi_va[0]])
>  

My concern about this is that it will break, or rather need to be changed
again for the 20.11 release. While I see the numbering as not-ideal in
terms of version numbers, the existing scheme was originally designed to
work with either 3-digit or 2-digit version numbers.

/Bruce