[LLVMdev] clang build (Debug+Asserts) fails with Cygwin and Mingw (ASTContext.o: File too big)

Tue May 6 04:20:49 PDT 2014

Hi Liviu
Le 04/05/2014 12:36, Liviu Gheorghisan a écrit :
>
>
> The problem is that, although ASTContext.o is built successfully with 
> -mbig-obj, the build fails later on in clang/unittests, like this:
>
> For this latter problem ("string table overflow"), I didn't yet find a 
> solution, apart from building without debug info, and with 
> optimizations enabled. See this also: 
> http://stackoverflow.com/questions/14125007/gcc-string-table-overflow-error-during-compilation
>
> I will switch back to Linux.
You can use the -Og option from g++.. It optimizes the space of the 
generated code while keeping all structures for gdb...see below the tail 
of the build
$ CXXFLAGS=-Og make -j3
...
...
make[3]: Leaving directory 
'/cygdrive/z/dev/llvm/x64/debug/unittests/Transforms/Utils'
make[2]: Leaving directory 
'/cygdrive/z/dev/llvm/x64/debug/unittests/Transforms'
llvm[2]: Compiling ThreadLocalTest.cpp for Debug+Asserts build
llvm[2]: Compiling TimeValueTest.cpp for Debug+Asserts build
llvm[2]: Compiling UnicodeTest.cpp for Debug+Asserts build
llvm[2]: Compiling YAMLIOTest.cpp for Debug+Asserts build
llvm[2]: Compiling YAMLParserTest.cpp for Debug+Asserts build
llvm[2]: Compiling formatted_raw_ostream_test.cpp for Debug+Asserts build
llvm[2]: Compiling raw_ostream_test.cpp for Debug+Asserts build
llvm[2]: Linking Debug+Asserts unit test Support
llvm[2]: ======= Finished Linking Debug+Asserts Unit test Support
make[2]: Leaving directory 
'/cygdrive/z/dev/llvm/x64/debug/unittests/Support'
make[1]: Leaving directory '/cygdrive/z/dev/llvm/x64/debug/unittests'
make[1]: Entering directory '/cygdrive/z/dev/llvm/x64/debug/projects'
make[1]: Nothing to be done for 'all'.
make[1]: Leaving directory '/cygdrive/z/dev/llvm/x64/debug/projects'
make[1]: Entering directory '/cygdrive/z/dev/llvm/x64/debug/bindings'
make[1]: Nothing to be done for 'all'.
make[1]: Leaving directory '/cygdrive/z/dev/llvm/x64/debug/bindings'
llvm[0]: ***** Completed Debug+Asserts Build
llvm[0]: ***** Note: Debug build can be 10 times slower than an
llvm[0]: ***** optimized build. Use make ENABLE_OPTIMIZED=1 to
llvm[0]: ***** make an optimized build. Alternatively you can
llvm[0]: ***** configure with --enable-optimized.


>
> On 5/3/2014 12:42 AM, Liviu Gheorghisan wrote:
>>
>>
>> On 5/2/2014 11:41 PM, David Blaikie wrote:
>>> Any idea what all those sections are - comdat inline functions?
>>>
>> No idea, as I cannot run objdump -h on a object file that I couldn't
>> build :)
>>   Anyhow, I have an old, successful Debug+Asserts build of clang, made
>> with Mingw also, for clang revision 206070. Apparently, the ASTContext.o
>> file there contained 16453 sections, not 33066, as there are today.
>>
>>> Does the debug info in COFF do something weird and emit a section per
>>> type or function?
>>>
>> I will do a release build tomorrow and check the sections. (in my
>> timezone it's night) - I will let you know!
>>
>>> On Fri, May 2, 2014 at 1:11 PM, Liviu Gheorghisan <livghe at gmx.com> 
>>> wrote:
>>>> Hello,
>>>>
>>>> After switching from a Linux development host to Windows7 with 
>>>> Cygwin, I
>>>> notice the following problem when building clang (trunk, HEAD):
>>>> (also happens with Mingw)
>>>>
>>>> ...
>>>>
>>>> llvm[4]: Compiling ParseInit.cpp for Debug+Asserts build
>>>> as:
>>>> /cygdrive/d/Projects/Cpp/llvm/cfgCygwin/tools/clang/lib/AST/Debug+Asserts/ASTContext.o: 
>>>>
>>>>
>>>> too many sections (33066)
>>>> /tmp/ccmtDH7w.s: Assembler messages:
>>>> /tmp/ccmtDH7w.s: Fatal error: can't write
>>>> /cygdrive/d/Projects/Cpp/llvm/cfgCygwin/tools/clang/lib/AST/Debug+Asserts/ASTContext.o: 
>>>>
>>>>
>>>> File too big
>>>> as:
>>>> /cygdrive/d/Projects/Cpp/llvm/cfgCygwin/tools/clang/lib/AST/Debug+Asserts/ASTContext.o: 
>>>>
>>>>
>>>> too many sections (33066)
>>>> /tmp/ccmtDH7w.s: Fatal error: can't close
>>>> /cygdrive/d/Projects/Cpp/llvm/cfgCygwin/tools/clang/lib/AST/Debug+Asserts/ASTContext.o: 
>>>>
>>>>
>>>> File too big
>>>> /cygdrive/d/Projects/Cpp/llvm/Makefile.rules:1509: recipe for target
>>>> '/cygdrive/d/Projects/Cpp/llvm/cfgCygwin/tools/clang/lib/AST/Debug+Asserts/ASTContext.o' 
>>>>
>>>>
>>>> failed
>>>> make[4]: ***
>>>> [/cygdrive/d/Projects/Cpp/llvm/cfgCygwin/tools/clang/lib/AST/Debug+Asserts/ASTContext.o] 
>>>>
>>>>
>>>> Error 1
>>>> make[4]: Leaving directory
>>>> '/cygdrive/d/Projects/Cpp/llvm/cfgCygwin/tools/clang/lib/AST'
>>>> /cygdrive/d/Projects/Cpp/llvm/Makefile.rules:936: recipe for target
>>>> 'AST/.makeall' failed
>>>> make[3]: *** [AST/.makeall] Error 2
>>>>
>>>> ...
>>>>
>>>>
>>>> The reason for this seems to be that the COFF object format in
>>>> Windows only
>>>> supports a maximum of 2^15 sections (32768) for obj files.
>>>>
>>>> To work around this issue, Microsoft's compiler cl has a flag called
>>>> /bigobj
>>>> that allocates 32 bits in order to store the number of sections
>>>> (instead of
>>>> 16 bits, as this standard specifies:
>>>> http://msdn.microsoft.com/en-us/library/gg463119.aspx )
>>>>
>>>> Also check this for /bigobj:
>>>> http://msdn.microsoft.com/en-us/library/ms173499.aspx
>>>>
>>>> Anybody else having this problem with Mingw/Cygwin? If yes, how did 
>>>> you
>>>> overcome it?
>>>>
>>>> My Cygwin version is this:
>>>> $ uname -a
>>>> CYGWIN_NT-6.1 livghe-i5 1.7.29(0.272/5/3) 2014-04-07 13:46 x86_64 
>>>> Cygwin
>>>>
>>>> The only option I currently see is to split the mammoth cpp file
>>>> (ASTContext.cpp)  in 2 parts, or to get rid of the debug info (not
>>>> desired).
>>>>
>>>>
>>>> -- 
>>>> Best Regards,
>>>> -Liviu
>>>> _______________________________________________
>>>> LLVM Developers mailing list
>>>> LLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.edu
>>>> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev
>>
>