llvm dev - Oct 2009 - [LLVMdev] Problem initializing a JIT via C bindings

Hi all,

I have some code that uses the x86 JIT via the C bindings that I'm trying to
migrate from targeting LLVM 2.5 to the top of tree, but I'm running into a
linking problem I can't figure out.

Here's how I'm invoking the JIT in 2.5.

LLVMInitializeNativeTarget(); <-- for the updated version
LLVMCreateMemoryBufferWithContentsOfFile("code.bc", &buffer,
&err);
LLVMGetBitcodeModuleProvider(buffer, &provider, &err);
LLVMCreateJITCompiler(&engine, provider, 1, &err);

After that LLVMFindFunction and RunFunction work wonderfully on 2.5.  The TOT
version errors out on the CreateJITCompiler call with a "JIT has not been
linked in" message.

I'm compiling it as follows, which completes with no errors on either LLVM
version.

LLVM_CONFIG=<the llvm-config from the version I want to use>
gcc `$LLVM_CONFIG --cflags` -o main.o -c main.c
g++ `$LLVM_CONFIG --cflags` \
    `$LLVM_CONFIG --ldflags` \
    main.o `$(LLVM_CONFIG) --libfiles engine BitReader`

Am I missing some other post 2.5 API change or am I building things wrong?

Thanks,

- Dave

Keppler, Dave wrote:
> Hi all,
> 
> I have some code that uses the x86 JIT via the C bindings that I'm
trying to migrate from targeting LLVM 2.5 to the top of tree, but I'm
running into a linking problem I can't figure out.
> 
> Here's how I'm invoking the JIT in 2.5.
> 
> LLVMInitializeNativeTarget(); <-- for the updated version
> LLVMCreateMemoryBufferWithContentsOfFile("code.bc", &buffer,
&err);
> LLVMGetBitcodeModuleProvider(buffer, &provider, &err);
> LLVMCreateJITCompiler(&engine, provider, 1, &err);
> 
> After that LLVMFindFunction and RunFunction work wonderfully on 2.5.  The
TOT version errors out on the CreateJITCompiler call with a "JIT has not
been linked in" message.
> 
> I'm compiling it as follows, which completes with no errors on either
LLVM version.
> 
> LLVM_CONFIG=<the llvm-config from the version I want to use>
> gcc `$LLVM_CONFIG --cflags` -o main.o -c main.c
> g++ `$LLVM_CONFIG --cflags` \
>     `$LLVM_CONFIG --ldflags` \
>     main.o `$(LLVM_CONFIG) --libfiles engine BitReader`
> 
> Am I missing some other post 2.5 API change or am I building things wrong?
Add "jit native" to the list of components you're passing to
llvm-config.

Nick

>> I'm compiling it as follows, which completes with no errors on
either
>LLVM version.
>>
>> LLVM_CONFIG=<the llvm-config from the version I want to use>
>> gcc `$LLVM_CONFIG --cflags` -o main.o -c main.c
>> g++ `$LLVM_CONFIG --cflags` \
>>     `$LLVM_CONFIG --ldflags` \
>>     main.o `$(LLVM_CONFIG) --libfiles engine BitReader`
>>
>> Am I missing some other post 2.5 API change or am I building things
>wrong?
>
>Add "jit native" to the list of components you're passing to
llvm-config.
>
>Nick
For me 'jit native' and 'engine' produce equivalent lists of
libraries.

Did my code look correct otherwise?  There must be something broken on my system
if that's the case.

- Dave