Re: [OE-core] Current native SDK glibc compat

["Richard Purdie" <richard.purdie@linuxfoundation.org>]

On Wed, 2021-02-24 at 13:56 +0100, Anatol Belski wrote:
> On 2/24/2021 1:32 PM, Richard Purdie wrote:
> > Hi,
> > 
> > On Wed, 2021-02-24 at 12:40 +0100, Anatol Belski wrote:
> > > the current master build seems to be broken with symbols unavailable
> > > from the host glibc. The following is to see on the SDK built and
> > > installed on the same host Ubuntu 18.04.5 having glibc 2.27:
> > > 
> > > $ . /tmp/poky-sdk-master-00/environment-setup-core2-64-poky-linux
> > > 
> > > $ ldd $(which $CC)
> > > /tmp/poky-sdk-master-00/sysroots/x86_64-pokysdk-linux/usr/bin/x86_64-poky-linux/x86_64-poky-linux-gcc:
> > > /lib/x86_64-linux-gnu/libc.so.6: version `GLIBC_2.33' not found
> > We change the loader path inside our SDK binaries so you can't trust the
> > output from ldd, it will find a different result to what you'd see
> > when you run the binary.
> > 
> > What issue are you seeing trying to run these?
> 
> Initially it was sighted here appearing when a binary is actually invoked:
> 
> https://github.com/meta-rust/meta-rust/pull/313#issuecomment-782784056
> 
> I went digging to see similar cases.
> 
> 
> Regarding the loader path, are you referring to this?
> 
> $ chrpath $(which $CC)
> /tmp/poky-sdk-master-00/sysroots/x86_64-pokysdk-linux/usr/bin/x86_64-poky-linux/x86_64-poky-linux-gcc: 
> RPATH=$ORIGIN/../../lib

No, I mean the dynamic loader pointer.

$ tmp/sysroots-uninative/x86_64-linux/usr/bin/patchelf-uninative python3-native/python3.9 --print-interpreter
[...]tmp/sysroots-uninative/x86_64-linux/lib/ld-linux-x86-64.so.2

Above I'm showing that a native binary in the build (python3-native)
has the interpreter (dynamic loader) set to our uninative ld.so.
The SDK is similar.

> As the binary where the issue was sighted has this
> 
> $ chrpath $(which cargo)
> /tmp/rust-sdk-deploy-18/sysroots/x86_64-pokysdk-linux/usr/bin/cargo: 
> RUNPATH=$ORIGIN/../lib
> 
> 
> but then, the DSOs have no rpath set, eg.
> 
> $ chrpath 
> /tmp/rust-sdk-deploy-18/sysroots/x86_64-pokysdk-linux/usr/bin/../lib/libcrypto.so.1.1
> /tmp/rust-sdk-deploy-18/sysroots/x86_64-pokysdk-linux/usr/bin/../lib/libcrypto.so.1.1: 
> no rpath or runpath tag found.
> 
> 
> so it might lead to the interferrence with the host. Does it perhaps 
> need both $ORIGIN/../../lib and $ORIGIN/../lib if binaries are in /usr ?

Our dynamic loader knows how to use the specific sysroot and then 
fall back to /usr and /lib.

Cheers,

Richard