Issue generating working sdk containing Clang (meta-clang) and package_deb for compiling eBPF #yocto #sdk #linux #dunfell #kernel


msg board
 

Hello,

I need Clang compiler apart from currently available default gcc compiler as I am trying to compile eBPF which will run on my custom yocto which is based on core-image-minimal. Therefore I added Clang compiler to my yocto sdk build using the meta-clang layer available at https://github.com/kraj/meta-clang . My yocto is based on dunfell and uses package_deb inside local.conf. SDK compilation succeeded with command "bitbake <mycustomdistro> -c populate_sdk " but while installation on host there errors similar to the ones mentioned in this issue .  Therefore, I removed the LDFLAGS_append_class-nativesdk = " -fuse-ld=gold" line from clang_git.bb and compiled. This gave me errors related to this issue . Therefore, I added package_ipk and also kept package_deb . The compilation was successful but there was one warning as below :

-------------------------

<CUSTOMDISTRO> do_populate_sdk: Unable to install packages. Command <Path>/opkg --volatile-cache -f <Path>/opkg.conf -t <Path>/sysroots/core2-64-poky-linux --force-postinstall --prefer-arch-to-version install <Long list of space seperate package names> returned 1

Collected errors: Solver encountered 1 problem(s) ....

 

 

 

-------------------------

The installation of on host was successful

When I tried to use the sdk to compile eBPF, I got errors mentioning that the sysroot does not contain /usr/include/gelf.h . After looking I saw that elfutils-dev tools were not installed. elfutils-dev would have installed gelf.h. in /usr/include of sysroot.

Without the addition of Clang I was able to generate working sdk with just package_deb in local.conf. 


Khem Raj
 

Hi

Can you try this patch ( if you are using master ) and see if that helps

diff --git a/recipes-devtools/clang/clang_git.bb
b/recipes-devtools/clang/clang_git.bb
index b8986be..b0c81f1 100644
--- a/recipes-devtools/clang/clang_git.bb
+++ b/recipes-devtools/clang/clang_git.bb
@@ -15,7 +15,6 @@ BUILD_CXX_class-nativesdk = "clang++"
BUILD_AR_class-nativesdk = "llvm-ar"
BUILD_RANLIB_class-nativesdk = "llvm-ranlib"
BUILD_NM_class-nativesdk = "llvm-nm"
-LDFLAGS_append_class-nativesdk = " -fuse-ld=lld"

inherit cmake cmake-native pkgconfig python3native

On Sat, Apr 3, 2021 at 3:34 PM msg board <msgboardpana@gmail.com> wrote:

Hello,

I need Clang compiler apart from currently available default gcc compiler as I am trying to compile eBPF which will run on my custom yocto which is based on core-image-minimal. Therefore I added Clang compiler to my yocto sdk build using the meta-clang layer available at https://github.com/kraj/meta-clang . My yocto is based on dunfell and uses package_deb inside local.conf. SDK compilation succeeded with command "bitbake <mycustomdistro> -c populate_sdk " but while installation on host there errors similar to the ones mentioned in this issue . Therefore, I removed the LDFLAGS_append_class-nativesdk = " -fuse-ld=gold" line from clang_git.bb and compiled. This gave me errors related to this issue . Therefore, I added package_ipk and also kept package_deb . The compilation was successful but there was one warning as below :

-------------------------

<CUSTOMDISTRO> do_populate_sdk: Unable to install packages. Command <Path>/opkg --volatile-cache -f <Path>/opkg.conf -t <Path>/sysroots/core2-64-poky-linux --force-postinstall --prefer-arch-to-version install <Long list of space seperate package names> returned 1

Collected errors: Solver encountered 1 problem(s) ....







-------------------------

The installation of on host was successful

When I tried to use the sdk to compile eBPF, I got errors mentioning that the sysroot does not contain /usr/include/gelf.h . After looking I saw that elfutils-dev tools were not installed. elfutils-dev would have installed gelf.h. in /usr/include of sysroot.

Without the addition of Clang I was able to generate working sdk with just package_deb in local.conf.