Question

I am trying to build the tests for rapidjson 0.11 (http://code.google.com/p/rapidjson/) on Mac OS X . It includes three projects: gtest (builds fine), unittest (build fails), and perftest (build fails), and when building make error out with Error 1 and Error 2.

The compiler output shows the following errors for both unittest and perftest which causes make to fail:

../../include/rapidjson/reader.h: In function ‘const char* rapidjson::SkipWhitespace_SIMD(const char*)’:
../../include/rapidjson/reader.h:116: error: ‘_SIDD_UBYTE_OPS’ was not declared in this scope
../../include/rapidjson/reader.h:116: error: ‘_SIDD_CMP_EQUAL_ANY’ was not declared in this scope
../../include/rapidjson/reader.h:116: error: ‘_SIDD_BIT_MASK’ was not declared in this scope
../../include/rapidjson/reader.h:116: error: ‘_SIDD_NEGATIVE_POLARITY’ was not declared in this scope

These pre-processor constants are related to SSE4 instructions. rapidjson can use SSE2 or SSE4.2 to speed it up, and it defaults to using SSE4.2 when building.

The makefile includes the -msse4.2 compiler switch to enable SSE4.2 support, and looking through the header files reveal that on OS X, both SSE4_1 and SSE4_2 pre-processor constants need to be defined for the SIDD… constants to be defined. For some reason, these SIDD… constants aren’t being defined.

Further research showed that the -msse4 switch enables support for both SSE4.1 and SSE4.2, so I tried chaning the switch to -msse4, but it still errors out.

Not sure if the -msse4.2 switch automatically defines SSE4_2 , but I tried manually defining it, and sill no luck.

NOTE: If you want to try building it yourself on Mac, you will need to download a different premake script file, as the included one doesn’t work. You can download the corrected script from the attachment on the second post here https://code.google.com/p/rapidjson/issues/detail?id=54

Any ideas on how to get it building successfully on OS X ?

Answer 1

Short answer – I had an older version of gcc (4.2) which didn’t support -msse4.2 flag (it was introduced in gcc 4.3).

After upgrading to the latest version of gcc, the above issue disappeared:

1. Check which version of gcc is active with by opening a terminal and
   running gcc -v
2. Download MacProst installer for your version of OS X from http://www.macports.org/install.php and run installer (easy way to upgrade GCC version)
3. Open new terminal window (must be new as PATH environment var is updated after MacPorts
   install)
4. Check which versions of gcc you already have installed with port select --list gcc (NOTE: you probably won’t have some of the later versions installed already. See next step)
5. Install latest version of gcc (gcc47 at the moment) with sudo port install gcc47 (this will take a while to download)
6. Run port select --list gcc again and you should see the new version in the list (eg. mp-gcc47)
7. Select this latest version as active gcc version with sudo port select gcc mp-gcc47
8. Run gcc -v again to check the latest version is active

With the compiler sorted, the first attempt to build rapidjson for release32 gave me errors about the limits header file due to __int128 not being defined for 32-bit builds`. Gnu’s official position is that you need to roll your own. See answers at following link for more info:

Compiling 32bit binary: expected unqualified-id before '__int128'

Building for release64 or debug64 solved this issue, but it still failed to build due some warnings about casting away qualifiers in test/unittest/readertest.cpp:187:4. As the make file included the compiler flag -Werror=cast-qual, these warnings were treated as errors. Removing this flag in both unittest and perftest makefiles solved this issue (not ideal solution but I just wanted to get it building).

There were still linker warnings as the /usr/lib64 folder didn’t exist, and the makefiles included the flag -L/usr/lib64, but the build was still successful.

SUCCESS – Both unittest_release_x64_gmake and perftest_release_x64_gmake ran without problems!

NOTE: rapidjson build instructions are included in the readme file in the ZIP archive.