[llvm-dev] Linking lld into embedded ARM application

[Viorel Preoteasa via llvm-dev]

Hello,

I have an embedded application for ARM architecture and I want to embed 
into it the lld linker. I have downloaded 
clang+llvm-11.0.1-armv7a-linux-gnueabihf.tar.xz and I have tried to add 
the following function to my application:

bool testLlvm()
{
     printf("test llvm\n");
     llvm::ArrayRef<const char*> args;
     bool canExitEarly = true;
     std::string s, t;
     llvm::raw_string_ostream stdoutOS(s);
     llvm::raw_string_ostream stderrOS(t);
     bool ret = lld::elf::link(args, canExitEarly, stdoutOS, stderrOS);
     printf("Output: %s\n", stdoutOS.str().c_str());
     printf("Error: %s\n", stderrOS.str().c_str());
     return ret;
}

The embedded application is  compiled using gcc, and I tried to link it 
to the llvm libraries. For linking I used all libraries liblld*.a and 
all libraries libLLVM*.a, however I got many linking errors of undefined 
symbols (listed at the end of the message).

Is it possible to link the existing llvm binary to the existing 
application using gcc? If so, what libraries are missing? Should I 
compile also llvm with gcc?

Actually, I realized now there is "linux" in the name of the binary 
distribution. My embedded device does not have Linux.

Is it possible at all to achieve this? The application compiler must be gcc.

Best regards,

Viorel

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