Add a config.h, containing GPOS_DEBUG and other flags that affect ABI.

[hlinnaka]

Before this patch, consumers of libgpos had to know out-of-band which
flags were used to compile libgpos, because e.g. libgpos compiled with
GPOS_DEBUG would only work if the application using libgpos was also
compiled with GPOS_DEBUG. This is because many of the structs differ
depending on GPOS_DEBUG. Same for the architecture flags, like GPOS_i386.

The new config.h file is #included from a few central other header files,
to make sure it gets included in any application that uses other gpos
headers. We probably should include config.h from all other gpos header
files, to be sure, but this seems to be enough for ORCA and GPDB at least.

[gpdbdreddbot]

Hello hlinnaka!

Thanks for submitting this pull request! I'm here to inform the recipients of the pull request that you've already signed the CLA.

[hlinnaka]

This is the same as PR #29. Let's see if it works this time. I have no idea what problem caused it to be reverted the first time 'round.

@d, please have a look.

[hlinnaka]

See also https://github.com/greenplum-db/gporca/pull/71

[d]

-1

This looks like it will fail when the build type is debug. Can you try building both PR under CMake Build Type debug and run tests? My hunch is that orca won't even link

[hlinnaka]

On 08/15/2016 05:15 PM, Jesse Zhang wrote:

-1

This looks like it will fail when the build type is debug. Can you
try building both PR under CMake Build Type debug and run tests? My
hunch is that orca won't even link

Works fine for me.

Can you please explain what the problem is that you're seeing? Are you
seeing an error? What is the error message?

• Heikki

[d]

when you configure GPOS with:
cmake -DCMAKE_BUILD_TYPE=Debug /path/to/gpos

The generated / installed gpos/config.h will NOT contain the macro GPOS_DEBUG, this will cause ORCA test failure and (in the best case) linking error

[d]

The following past failed build might be of value to you, @hlinnaka https://gporca.ci.pivotalci.info/pipelines/gporca/jobs/orca_centos5_debug/builds/9

In Linux we were able to link, but the resulting binary was failing all tests (obviously)

[hlinnaka]

On 08/15/2016 07:44 PM, Jesse Zhang wrote:

when you configure GPOS with:
cmake -DCMAKE_BUILD_TYPE=Debug /path/to/gpos

The generated / installed gpos/config.h will NOT contain the macro
GPOS_DEBUG, this will cause ORCA test failure and (in the best
case) linking error

A-ha, I didn't know about CMAKE_BUILD_TYPE! I had used just "cmake
-DGPOS_DEBUG=1". Thanks!

I'm baffled why that led to a linking error, though. I would expect ORCA
to just not be built with GPOS_DEBUG. In any case, I pushed a change
to this PR, to set GPOS_DEBUG, when CMAKE_BUILD_TYPE is Debug. Please
have a look.

• Heikki

[d]

I'm not baffled how that could lead to linking error: it's C/C++ with #ifdef/#ifndef, which means your ABI is not constant, anything goes. In our case, the ABI varies depending on both the value of GPOS_DEBUG macro and the value of GPOS_DEBUG CMake variable.

[hlinnaka]

On 21 August 2016 07:45:18 EEST, Jesse Zhang notifications@github.com wrote:

I'm not baffled how that could lead to linking error: it's C/C++ with
#ifdef/#ifndef, which means your ABI is not constant, anything
goes. In our case, the ABI varies depending on both the value of
GPOS_DEBUG macro and the value of GPOS_DEBUG CMake variable.

How does the cmake variable affect the ABI?

Do you still see a problem with this latest patch?

• Heikki