[Bug] undeclared identifier 'RTLD_DI_LOAD_ADDR' while compiling for Hexagon

[aryamazaheri]

While compiling TVM for Hexagon backend, I get the following error:

/home/osboxes/tvm/src/runtime/dso_library.cc:129:32: error: use of undeclared identifier 'RTLD_DI_LOAD_ADDR'
  int rc = dlinfo(lib_handle_, RTLD_DI_LOAD_ADDR, &p);

Environment

OS: Ubuntu 18.04
TVM: 0.13
Hexagon SDK: 5.3.0.0

Steps to reproduce

HEXAGON_SDK_ROOT=$HOME/Hexagon/5.3.0.0; \
DEFAULT_HEXAGON_TOOLS_ROOT=$HEXAGON_SDK_ROOT/tools/HEXAGON_Tools/8.6.06; \
CC=$DEFAULT_HEXAGON_TOOLS_ROOT/Tools/bin/hexagon-clang; \
CXX=$DEFAULT_HEXAGON_TOOLS_ROOT/Tools/bin/hexagon-clang++;\
CXXFLAGS='-stdlib=libc++ -I${HEXAGON_SDK_ROOT}/rtos/qu^C/computev69/include/posix -I${HEXAGON_SDK_ROOT}/rtos/qurt/computev69/include/qurt'; \
cmake .. -DCMAKE_SYSTEM_NAME=Linux -DCMAKE_SYSTEM_VERSION=1 -DCMAKE_C_COMPILER=$DEFAULT_HEXAGON_TOOLS_ROOT/Tools/bin/hexagon-clang -DCMAKE_CXX_COMPILER=$DEFAULT_HEXAGON_TOOLS_ROOT/Tools/bin/hexagon-clang++ -DUSE_RPC=OFF -DUSE_LLVM=OFF

Triage

• vert:hexagon

[masahi]

cc @kparzysz-quic

[abhikran-quic]

Hi @aryamazaheri ,

I'm trying to check this error and unable to reproduce the problem you've mentioned.

Request you to please help in sharing insights on the following questions:

1. The command shared by you gives me a different error

tvm/src/ir/diagnostic.cc:27:
tvm/3rdparty/rang/include/rang.hpp:11:2: error: Unknown Platform
#error Unknown Platform
 ^
tvm/3rdparty/rang/include/rang.hpp:163:16: error: use of undeclared identifier 'result'
        return result;
               ^
2 errors generated.

Not sure if you have seen the same error and have a fix for this ?

2. Are you trying to build TVM runtime for hexagon ? Or do you want to build TVM so that it can generate code for hexagon backend ?

[aryamazaheri]

Hi @abhikran-quic ,

1. I never faced with this problem. Could it be because of -DCMAKE_SYSTEM_NAME=Linux in the cmake command?
2. I am trying to build the runtime for hexagon. I have a compute board with Qualcomm SoC and I need to cross compile TVM runtime with hexagon support so that I can run TVM on it.

[abhikran-quic]

Thanks @aryamazaheri for sharing the details.

1. The problem went away after removing -DCMAKE_SYSTEM_NAME=Linux flag and I was able to reproduce the issue.
2. The issue is seen because a different version of dlfcn.h is being picked up while compilation. Ideally it should be picked up from $HEXAGON_SDK_ROOT/ipc/fastrpc/rtld/ship/inc which contains RTLD_DI_LOAD_ADDR definition. Could you please try with the below mentioned command?

HEXAGON_SDK_ROOT=$HOME/Hexagon/5.3.0.0; \
DEFAULT_HEXAGON_TOOLS_ROOT=$HEXAGON_SDK_ROOT/tools/HEXAGON_Tools/8.6.06; \
CC=$DEFAULT_HEXAGON_TOOLS_ROOT/Tools/bin/hexagon-clang; \
CXX=$DEFAULT_HEXAGON_TOOLS_ROOT/Tools/bin/hexagon-clang++;\
cmake .. \
	-DCMAKE_SYSTEM_VERSION=1 \
	-DCMAKE_C_COMPILER=$DEFAULT_HEXAGON_TOOLS_ROOT/Tools/bin/hexagon-clang \
	-DCMAKE_CXX_COMPILER=$DEFAULT_HEXAGON_TOOLS_ROOT/Tools/bin/hexagon-clang++ \
	-DUSE_RPC=OFF -DUSE_LIBBACKTRACE=OFF -DUSE_LLVM=OFF \
	-DCMAKE_CXX_FLAGS="-isystem $HEXAGON_SDK_ROOT/incs \
		-isystem $HEXAGON_SDK_ROOT/incs/stddef \
		-isystem $HEXAGON_SDK_ROOT/rtos/qurt/computev68/include/posix \
		-isystem $HEXAGON_SDK_ROOT/rtos/qurt/computev68/include/qurt \
		-isystem $HEXAGON_SDK_ROOT/ipc/fastrpc/rtld/ship/inc \
		-stdlib=libc++"

make runtime -j${nproc}

[kparzysz-quic]

There is code in cmake/modules/HexagonSDK.cmake that is supposed to add the correct paths. If removing CMAKE_SYSTEM_NAME makes it work, then that's probably the easiest (and the right) thing to do. The system name flag may be inserting additional include paths that cause the wrong header to be included. The TVM runtime for Hexagon is not running on Linux, so setting the system name to Linux is incorrect even in the absence of any issues.

[aryamazaheri]

Many thanks, @abhikran-quic . I can now build tvm for hexagon. Maybe we should update the readme file in src/runtime/hexagon/README.md to contain these flags?

[abhikran-quic]

Sure @aryamazaheri . We have raised #14948 to fix this.

[aryamazaheri]

Great, many thanks