Re: [Tarantool-patches] [PATCH v1] Block linker flag '--no-undefined'

[Igor Munkin <imun@tarantool.org>]

Sasha,

Thanks for the patch!

On 06.07.20, Alexander V. Tikhonov wrote:
> Found that opensuse adding linker flag '--no-undefined' which produces
> the fails on building tests. Decided to block this flag due to dynamic
> libraries will be loaded from tarantool executable and will use symbols
> from it. So it is completely okay to have unresolved symbols at build
> time.

Minor: I reworded the message a bit:
| Found that OpenSUSE toolchain adds '--no-undefined' linked flag leading
| to fails while building tests. The changes suppress this flag since
| dynamic libraries are loaded via Tarantool executable and use its
| symbols. So it is completely OK to have undefined symbols at build time.
Feel free to adjust it on your own.

Also, it would be nice to add "test: " prefix to explicitly mention the
affected parts.

> 
> Relates to tarantool/tarantool#4562
> ---
> 
> Github: https://github.com/tarantool/luajit/tree/avtikhon/gh-4562-suse-block-linker-flag
> Issue: https://github.com/tarantool/tarantool/issues/4562
> 
>  test/gh-4427-ffi-sandwich/CMakeLists.txt | 1 +
>  test/lj-flush-on-trace/CMakeLists.txt    | 1 +
>  2 files changed, 2 insertions(+)
> 

Strictly saying, I see no reason to fix the problem here. These changes
are similar and one ought to add this "woodoo magic" line to every
CMakeLists.txt used for building dynamic libraries using Lua C API.
Since we are using <build_lualib> to build these extensions can you make
this change there?

> diff --git a/test/gh-4427-ffi-sandwich/CMakeLists.txt b/test/gh-4427-ffi-sandwich/CMakeLists.txt
> index 995c6bb..6028381 100644
> --- a/test/gh-4427-ffi-sandwich/CMakeLists.txt
> +++ b/test/gh-4427-ffi-sandwich/CMakeLists.txt
> @@ -1 +1,2 @@
> +string(REPLACE "-Wl,--no-undefined" "" CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS}")
>  build_lualib(libsandwich libsandwich.c)
> diff --git a/test/lj-flush-on-trace/CMakeLists.txt b/test/lj-flush-on-trace/CMakeLists.txt
> index a90452d..4f2f956 100644
> --- a/test/lj-flush-on-trace/CMakeLists.txt
> +++ b/test/lj-flush-on-trace/CMakeLists.txt
> @@ -1 +1,2 @@
> +string(REPLACE "-Wl,--no-undefined" "" CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS}")
>  build_lualib(libflush libflush.c)
> -- 
> 2.17.1
> 

-- 
Best regards,
IM