llvm dev - Sep 2011 - [LLVMdev] LLVMHello pass compile error under Cygwin

I've built LLVM/Clang from svn under Cygwin on Windows 7. I'd like to
build on the LLVMHello pass example, however, when I try:

$ cd $LLVM/lib/Transforms/Hello
$ make

I receive a large number of errors which start with:

llvm[0]: Linking Debug+Asserts Loadable Module LLVMHello.dll
/cygdrive/c/Users/Graham/home/projects/llvm_cygwin/lib/Transforms/Hello/Debug+Asserts/Hello.o:
In function `runOnFunction':
/cygdrive/c/Users/Graham/home/projects/llvm_cygwin/lib/Transforms/Hello/Hello.cpp:32:
undefined reference to `llvm::errs()'
...

I've built and ran the same example under Linux with no problems. Does
anyone have an idea what the problem might be?

--
Graham

Graham, good morning.

To build LLVMHello on cygming, you should configure llvm with --enable-shared .

Even with enable-shared, you might build lib/Transforms/Hello manually.
(yeah, on cygming, LLVMHello should depend on tools/llvm-shlib)

And, you'd be better to build with --enable-optimized.
With enable-shared, llvm-shlib tends to fail with too many debug symbols.

HTH, ...Takumi

Thankyou Takumi,

Without --enable-optimized I get a"File too big" error from the
linker:

...
llvm[1]: Linking all LLVMLibs together for LLVM-3.0svn
/usr/lib/gcc/i686-pc-cygwin/4.5.3/../../../../i686-pc-cygwin/bin/ld:
/cygdrive/c/Users/Graham/home/projects/llvm_cygwin3/tools/llvm-shlib/Debug+Asserts/LLVM-3.0svn.a.o:
too many sections (59747)
/usr/lib/gcc/i686-pc-cygwin/4.5.3/../../../../i686-pc-cygwin/bin/ld:
final link failed: File too big
collect2: ld returned 1 exit status
make[1]: ***
[/cygdrive/c/Users/Graham/home/projects/llvm_cygwin3/tools/llvm-shlib
/Debug+Asserts/LLVM-3.0svn.a.o] Error 1
make[1]: Leaving directory
`/cygdrive/c/Users/Graham/home/projects/llvm_cygwin3/tools/llvm-shlib'
make: *** [all] Error 1

(By the way, I have 4Gb Ram under 64-bit Windows 7, and use Cygwin's GCC
4.5.3)

If I instead use --enable-optimized, everything builds, however any
invocation of clang.exe
now halts with a segmentation fault, as shown:

clang hello.c fails:
      0 [main] clang 3608 exception::handle: Exception: STATUS_ACCESS_VIOLATION
  10619 [main] clang 3608 open_stackdumpfile: Dumping stack trace to
clang.exe.stackdump
clang: error: unable to execute command: Segmentation fault (core dumped)
clang: error: clang frontend command failed due to signal 2 (use -v to
see invocation)
clang: note: diagnostic msg: Please submit a bug report to http://llvm.org/bugs/
 and include command line arguments and all diagnostic information.
clang: error: unable to execute command: Segmentation fault (core dumped)
clang: note: diagnostic msg: Error generating preprocessed source(s).

Can you offer a suggestion here? (I am happy to submit a bug report if
appropriate.)

Regards,
Graham