compile error when building --with-unixodbc (libfl.so: undefined reference to `yylex')

[okanisis]

Is this a bison/flex issue?

Linux archasus 3.12.13-1-ck #1 SMP PREEMPT Sat Feb 22 18:08:42 EST 2014 x86_64 GNU/Linux
bison (GNU Bison) 3.0.2
flex 2.5.38
unixodbc 2.3.2

I've tried compiling using --with-unixodbc=/usr/include, --with-unixodbc=/usr/lib and just --with-unixodbc but they result in same error.

Making all in odbc
make[2]: Entering directory '/tmp/makepkg/mdbtools-git/src/mdbtools/src/odbc'
  CC       odbc.lo
  CC       connectparams.lo
  CCLD     libmdbodbc.la
  CC       libmdbodbcW_la-odbc.lo
  CC       libmdbodbcW_la-connectparams.lo
  CCLD     libmdbodbcW.la
  CC       unittest.o
  CCLD     unittest
/usr/lib/gcc/x86_64-unknown-linux-gnu/4.8.2/../../../../lib/libfl.so: undefined reference to `yylex'
collect2: error: ld returned 1 exit status```

[nirgal]

On Debian, I'm using --with-unixodbc=/usr

libfl.so comes with flex.

Did you try running autoreconf -i -f then ./configure --with-unixodbc=/usr --disable-scrollkeeper ?

[okanisis]

@nirgal Thanks for those, I made those changes now and it still gives me the flex error, but it looks nicer:

Making all in odbc
make[2]: Entering directory '/tmp/makepkg/mdbtools-git/src/mdbtools/src/odbc'
  CC       odbc.lo
  CC       connectparams.lo
  CCLD     libmdbodbc.la
  CC       libmdbodbcW_la-odbc.lo
  CC       libmdbodbcW_la-connectparams.lo
  CCLD     libmdbodbcW.la
  CC       unittest.o
  CCLD     unittest
/usr/lib/libfl.so: undefined reference to `yylex'
collect2: error: ld returned 1 exit status
Makefile:452: recipe for target 'unittest' failed
make[2]: *** [unittest] Error 1

[okanisis]

FYI: I tried compiling against 0.7.1 and got the same error.

[enjolras]

Downgrading flex to 2.5.37 seems to work, per a comment in: https://aur.archlinux.org/packages/mdbtools/

[nirgal]

It looks like a common problem with flex:
http://sourceforge.net/p/flex/mailman/search/?q=undefined+reference+to+%60yylex%27

I can't reproduce the bug here, but it might be related to g++ compilation.

• Can you add "--disable-silent-rules" to your configure line and post the log of the make here, please?
• If this is indeed a c vs c++ compiler related problem, adding extern "C" block in the prototypes at the begining of src/sql/parser.y might help...

If downgrading flex fixes the issue helps, maybe this problem should be repported against flex?

[LukeShu]

The correct solution is to remove all references to @LEXLIB@ from the Makefiles.

The references to @LEXLIB@ have been wrong since ChangeLog entry 2001-09-29 Brian Bruns <camber@ais.org> (which was imported from CVS to Git in ea8fd2a). Since then, it should not link against -lfl. The Makefiles were linking it against -lfl anyway, which until now apparently didn't mess anything up.

[adamcrown]

I'm getting this same error on Arch Linux. Any updates on this?

[nirgal]

LukeShu: I don't understand. The Makefile's no longer are part of the project, you need to use autoreconf -i. They were generated files anyway. There no longer is any -lfl in the code. It's only added by autoreconf.

Can you elaborate?

[LukeShu]

Sorry I was unclear. By "Makefiles", I meant src/*/Makefile.am. The lex Autoconf macros automatically set @LEXLIB@ to the appropriate value for your system; with Flex that's -lfl. The Automake files include @LEXLIB@ in $LIBS even though they shouldn't.

Here's how the Parabola distro handles it: https://projects.parabola.nu/abslibre.git/tree/pcr/mdbtools/PKGBUILD#n26 (look at the prepare() function)

@adamcrown: Parabola is compatible with Arch; feel free to grab the binary or the PKGBUILD. I'll go ahead and add it to AUR4, but there's a solid chance that I'll forget to keep it up to date.

[evanmiller]

Duplicate of #81, fix included in #162