ubsan minimal runtime option and OpenJDK

[Magnus Ihse Bursie]

On 2024-10-09 09:39, Baesken, Matthias wrote:
>
> Hi,
>
> I wanted to try the "minimal runtime" option of ubsan because it might 
> be faster and has other benefits.
> See
> https://clang.llvm.org/docs/UndefinedBehaviorSanitizer.html#minimal-runtime 
> <https://clang.llvm.org/docs/UndefinedBehaviorSanitizer.html#minimal-runtime>
>
> Unfortunately it seems to be available only with clang on Linux, not 
> (yet?) gcc, so I configured
> --with-additional-ubsan-checks=-fsanitize-minimal-runtime 
> --with-toolchain-type=clang
>
> but after some compilation I run into this link error :
> jdk/lib/server/libjvm.so: undefined symbol: 
> __ubsan_handle_type_mismatch_minimal
>
> Any ideas what's wrong here ?
> https://github.com/systemd/systemd/issues/26975 
> <https://github.com/systemd/systemd/issues/26975>
> suggests that we might need to adjust the linker settings to allow 
> undefined symbols , not sure if this is the same issue ?
>
I'd say it looks like you need to link with another library? Where 
should the __ubsan_handle_type_mismatch_minimal symbol come from?
>
> On the other hand, I tried the minimal runtime option with some 
> standalone program examples outside the OpenJDK, and
>
> The error output was indeed  “minimal”   (without line numbers of the 
> error); so it looked not very useful to me  but this might be my 
> limited understanding.
>
So what you're saying is that it is not really worth spending any time 
on sorting this out?

/Magnus

> Any experience with this option ?
>
> Best regards, Matthias
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://mail.openjdk.org/pipermail/build-dev/attachments/20241028/2370f78c/attachment.htm>