BCC does not support LLVLM 7 or earlier anymore with the master branch

[viniciusd]

By trying to compile BCC on Ubuntu (both 18.04 and 20.04, GCC 7.5+llvm6 and GCC 9.3+llvm7, respectively), it fails as per the log:

/tmp/bcc/src/cc/bpf_module.cc: In member function ‘virtual void ebpf::MyMemoryManager::notifyObjectLoaded(llvm::ExecutionEngine*, const llvm::object::ObjectFile&)’:
/tmp/bcc/src/cc/bpf_module.cc:108:46: error: no matching function for call to ‘llvm::object::SectionRef::getName() const’
       auto sec_name = section.get()->getName();
                                              ^
In file included from /usr/lib/llvm-6.0/include/llvm/DebugInfo/DIContext.h:19:0,
                 from /usr/lib/llvm-6.0/include/llvm/ExecutionEngine/RuntimeDyld.h:19,
                 from /usr/lib/llvm-6.0/include/llvm/ExecutionEngine/RTDyldMemoryManager.h:19,
                 from /usr/lib/llvm-6.0/include/llvm/ExecutionEngine/SectionMemoryManager.h:20,
                 from /tmp/bcc/src/cc/bpf_module.cc:22:
/usr/lib/llvm-6.0/include/llvm/Object/ObjectFile.h:399:24: note: candidate: std::error_code llvm::object::SectionRef::getName(llvm::StringRef&) const
 inline std::error_code SectionRef::getName(StringRef &Result) const {
                        ^~~~~~~~~~
/usr/lib/llvm-6.0/include/llvm/Object/ObjectFile.h:399:24: note:   candidate expects 1 argument, 0 provided
src/cc/CMakeFiles/bcc-shared.dir/build.make:110: recipe for target 'src/cc/CMakeFiles/bcc-shared.dir/bpf_module.cc.o' failed
make[2]: *** [src/cc/CMakeFiles/bcc-shared.dir/bpf_module.cc.o] Error 1
CMakeFiles/Makefile2:234: recipe for target 'src/cc/CMakeFiles/bcc-shared.dir/all' failed
make[1]: *** [src/cc/CMakeFiles/bcc-shared.dir/all] Error 2
Makefile:140: recipe for target 'all' failed
make: *** [all] Error 2

Checking the autogenerated doxygen, I see indeed the function getName() does not have an argument anymore, but the headers for both llvm 7 and llvm 6 contain only std::error_code SectionRef::getName(StringRef &Result) const

This was changed in this commit of the llvm project (llvm/llvm-project@bcc00e1afbdc1). Looking at the releases history, I assume it was initially released in llvm9, as the commit dates to mid 2019.

BCC changed the usage of this getName function in the commit 8323d74 by @davemarchevsky, which was merged a couple of weeks ago to BCC's master branch.

Should BCC require llvm9+ now? Not sure what solution should the project adopt.

INSTALL.md suggested llvm6 for Ubuntu 18.04 and llvm7 for Ubuntu 19 or 20.

[chenhengqi]

see #3808

[viniciusd]

For whoever arrives here facing the same issue, download the release 0.24.0, it will compile successfully.

But check #3808 for future releases.

[asmca]

confirmed on similar platform to ubuntu 20.04 with llvm7.
also checked release 0.24.0 works.

[ulidtko]

v0.24.0 tag did not compile for me on bionic 18.04.6 LTS + LLVM 7.

$ lsb_release -a
No LSB modules are available.
Distributor ID:	Ubuntu
Description:	Ubuntu 18.04.6 LTS
Release:	18.04
Codename:	bionic

$ cmake BUILD
-- Latest recognized Git tag is v0.24.0
-- Git HEAD is 43fec8b8eddaf3dd8805ff0cfcf4bd031db60f38
-- Revision is 0.24.0-43fec8b8
-- Found LLVM: /usr/lib/llvm-7/include 7.0.0 (Use LLVM_ROOT envronment variable for another version of LLVM)
-- Could NOT find LibDebuginfod (missing: LIBDEBUGINFOD_LIBRARIES LIBDEBUGINFOD_INCLUDE_DIRS) 
-- Using static-libstdc++
-- Configuring done
-- Generating done
-- Build files have been written to: /home/dev-be/src/bcc/BUILD

Same error, different line:

/home/dev-be/src/bcc/src/cc/bpf_module.cc: In member function ‘virtual void ebpf::MyMemoryManager::notifyObjectLoaded(llvm::ExecutionEngine*, const llvm::object::ObjectFile&)’:
/home/dev-be/src/bcc/src/cc/bpf_module.cc:113:46: error: no matching function for call to ‘llvm::object::SectionRef::getName() const’
       auto sec_name = section.get()->getName();
                                              ^

---

Edit: got successful compile of v0.24.0 with newer LLVM 10.

[ulugbek5609]

Release v0.24.0 only compiled for me with focal 20.04 + LLVM 10. Could be useful: 3601 2340

[magichan]

ubuntu 18.04 and llvm 10, compile fail when checkout v0.24.0 from master ,

delete repo, and reclone the bcc based on v0.24.0 , got successful compile

( maybe the libbpf submodule affect

[sujankh]

I installed llvm-11 in Ubuntu 18.04 using llvm.sh script provided in https://apt.llvm.org/ . I was able to compile the latest bcc master successfully. I had to manually update CMakeLists to point to the new installation but the rest worked fine:

To install llvm-11:
NOTE: I had to remove libunwind-11-dev from the llvm.sh script because apt reported that it was unavailable for installation.

sudo ./llvm.sh 11 all

CMakeLists diff:

diff --git a/CMakeLists.txt b/CMakeLists.txt
index d5614896..65b95908 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -123,7 +123,7 @@ if(CMAKE_USE_LIBBPF_PACKAGE)
 endif()
 
 if(NOT PYTHON_ONLY)
-  find_package(LLVM REQUIRED CONFIG)
+  find_package(LLVM REQUIRED CONFIG HINTS /usr/lib/llvm-11/cmake)
   message(STATUS "Found LLVM: ${LLVM_INCLUDE_DIRS} ${LLVM_PACKAGE_VERSION} (Use LLVM_ROOT envronment variable for another version of LLVM)")
 
   if(ENABLE_CLANG_JIT)
@@ -138,7 +138,7 @@ if(NOT PYTHON_ONLY)
 
     # clang is linked as a library, but the library path searching is
     # primitively supported, unlike libLLVM
-    set(CLANG_SEARCH "/opt/local/llvm/lib;/usr/lib/llvm-3.7/lib;${LLVM_LIBRARY_DIRS}")
+    set(CLANG_SEARCH "/usr/lib/llvm-11/lib;${LLVM_LIBRARY_DIRS}")
     find_library(libclangAnalysis NAMES clangAnalysis clang-cpp HINTS ${CLANG_SEARCH})
     find_library(libclangAST NAMES clangAST clang-cpp HINTS ${CLANG_SEARCH})
     find_library(libclangBasic NAMES clangBasic clang-cpp HINTS ${CLANG_SEARCH})