Re: JIT compiling with LLVM v9.0

Hi,

On 2018-01-29 23:49:14 +0100, Tomas Vondra wrote:
> On 01/29/2018 11:17 PM, Andres Freund wrote:
> > On 2018-01-29 23:01:14 +0100, Tomas Vondra wrote:
> >> $ llvm-config --version
> >> 5.0.0svn
> >
> > Is thta llvm-config the one in /usr/local/include/ referenced by the
> > error message above?
>
> I don't see it referenced anywhere, but it comes from here:
>
> $ which llvm-config
> /usr/local/bin/llvm-config
>
> > Or is it possible that llvm-config is from a different version than
> > the one the compiler picks the headers up from?
> >
>
> I don't think so. I don't have any other llvm versions installed, AFAICS.

Hm.


> > could you go to src/backend/lib, rm llvmjit.o, and show the full output
> > of make llvmjit.o?
> >
>
> Attached.
>
> > I wonder whether the issue is that my configure patch does
> >         -I*|-D*) CPPFLAGS="$CPPFLAGS $pgac_option";;
> > rather than
> >         -I*|-D*) CPPFLAGS="$pgac_option $CPPFLAGS";;
> > and that it thus picks up the wrong header first?
> >
>
> I've tried this configure tweak:
>
>    if test -n "$LLVM_CONFIG"; then
>      for pgac_option in `$LLVM_CONFIG --cflags`; do
>        case $pgac_option in
> -        -I*|-D*) CPPFLAGS="$CPPFLAGS $pgac_option";;
> +        -I*|-D*) CPPFLAGS="$pgac_option $CPPFLAGS";;
>        esac
>      done
>
> and that indeed changes the failure to this:

Err, huh?  I don't understand how that can change anything if you
actually only have only one version of LLVM installed. Perhaps the
effect was just an ordering related artifact of [parallel] make?
I.e. just a question what failed first?


> Writing postgres.bki
> Writing schemapg.h
> Writing postgres.description
> Writing postgres.shdescription
> llvmjit_error.cpp: In function ‘void llvm_enter_fatal_on_oom()’:
> llvmjit_error.cpp:61:3: error: ‘install_bad_alloc_error_handler’ is not
> a member of ‘llvm’
>    llvm::install_bad_alloc_error_handler(fatal_llvm_new_handler);
>    ^~~~
> llvmjit_error.cpp: In function ‘void llvm_leave_fatal_on_oom()’:
> llvmjit_error.cpp:77:3: error: ‘remove_bad_alloc_error_handler’ is not a
> member of ‘llvm’
>    llvm::remove_bad_alloc_error_handler();
>    ^~~~
> llvmjit_error.cpp: In function ‘void llvm_reset_fatal_on_oom()’:
> llvmjit_error.cpp:92:3: error: ‘remove_bad_alloc_error_handler’ is not a
> member of ‘llvm’
>    llvm::remove_bad_alloc_error_handler();
>    ^~~~

It's a bit hard to interpret this without the actual compiler
invocation. But I've just checked both manually by inspecting 5.0 source
and by compiling against 5.0 that that function definition definitely
exists:

andres@alap4:~/src/llvm-5$ git branch
  master
* release_50
andres@alap4:~/src/llvm-5$ ack remove_bad_alloc_error_handler
lib/Support/ErrorHandling.cpp
139:void llvm::remove_bad_alloc_error_handler() {

include/llvm/Support/ErrorHandling.h
101:void remove_bad_alloc_error_handler();

So does my system llvm 5:
$ ack remove_bad_alloc_error_handler /usr/include/llvm-5.0/
/usr/include/llvm-5.0/llvm/Support/ErrorHandling.h
101:void remove_bad_alloc_error_handler();

But not in 4.0:
$ ack remove_bad_alloc_error_handler /usr/include/llvm-4.0/


> gcc -Wall -Wmissing-prototypes -Wpointer-arith -Wdeclaration-after-statement -Wendif-labels
-Wmissing-format-attribute-Wformat-security -fno-strict-aliasing -fwrapv -fexcess-precision=standard -g
-fno-omit-frame-pointer-O2 -I../../../src/include  -D_GNU_SOURCE -I/usr/local/include -DNDEBUG -DLLVM_BUILD_GLOBAL_ISEL
-D_GNU_SOURCE-D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS   -c -o llvmjit.o llvmjit.c
 
> llvmjit.c: In function ‘llvm_get_function’:
> llvmjit.c:239:45: warning: passing argument 2 of ‘LLVMOrcGetSymbolAddress’ from incompatible pointer type
[-Wincompatible-pointer-types]
>   if (LLVMOrcGetSymbolAddress(llvm_opt0_orc, &addr, mangled))
>                                              ^
> In file included from llvmjit.c:45:0:
> /usr/local/include/llvm-c/OrcBindings.h:129:22: note: expected ‘const char *’ but argument is of type
‘LLVMOrcTargetAddress* {aka long unsigned int *}’
 
>  LLVMOrcTargetAddress LLVMOrcGetSymbolAddress(LLVMOrcJITStackRef JITStack,
>                       ^~~~~~~~~~~~~~~~~~~~~~~

To me this looks like those headers are from llvm 4, rather than 5:
$ grep -A2 -B3 LLVMOrcGetSymbolAddress ~/src/llvm-4/include/llvm-c/OrcBindings.h
/**
 * Get symbol address from JIT instance.
 */
LLVMOrcTargetAddress LLVMOrcGetSymbolAddress(LLVMOrcJITStackRef JITStack,
                                             const char *SymbolName);

$ grep -A3 -B3 LLVMOrcGetSymbolAddress ~/src/llvm-5/include/llvm-c/OrcBindings.h
/**
 * Get symbol address from JIT instance.
 */
LLVMOrcErrorCode LLVMOrcGetSymbolAddress(LLVMOrcJITStackRef JITStack,
                                         LLVMOrcTargetAddress *RetAddr,
                                         const char *SymbolName);

So it does appear that your llvm-config and the actually installed llvm
don't quite agree. How did you install llvm?

Greetings,

Andres Freund