[gnutls-help] on finding nettle under /usr/local rather than under /usr (GNU+Linux 64-bit system)

[Marco Maggi]

Ciao,

  I am trying to install  Gnutls 3.2.0 on a GNU+Linux 64-bit
system with  Slackware's Nettle  2.5 installed  under "/usr"
and my own installation of Nettle 2.7.1 under "/usr/local".

  I can do:

   $ /sbin/ldconfig -p | grep nettle
   libnettle.so.4 (libc6,x86-64) => /usr/local/lib/libnettle.so.4
   libnettle.so.4 (libc6,x86-64) => /usr/lib64/libnettle.so.4
   libnettle.so (libc6,x86-64) => /usr/local/lib/libnettle.so
   libnettle.so (libc6,x86-64) => /usr/lib64/libnettle.so

so I  would expect Gnutls's building  infrastructure to find
the correct version, but instead  it does not happen.  I can
also do:

   $ pkg-config nettle --libs
   -L/usr/local/lib -lnettle
   $ pkg-config nettle --cflags
   -I/usr/local/include
   $ pkg-config libtasn1 --libs
   -L/usr/local/lib -ltasn1
   $ pkg-config libtasn1 --cflags
   -I/usr/local/include

  If I just do:

   $ ./configure

the build starts and it seems to find the right Nettle:

   $ grep nettle config.log
   configure:8886: checking whether to use nettle
   configure:9384: checking for libnettle
   configure:9406: gcc -std=gnu99 -o conftest -g -O2 -L/usr/local/lib conftest.c /usr/local/lib/libnettle.so /usr/local/lib/libhogweed.so -lgmp -Wl,-rpath -Wl,/usr/local/lib >&5
   configure:9423: checking how to link with libnettle
   configure:9425: result: /usr/local/lib/libnettle.so /usr/local/lib/libhogweed.so -lgmp -Wl,-rpath -Wl,/usr/local/lib
   config.status:3259: creating lib/nettle/Makefile
   ac_cv_libnettle=yes
   LIBNETTLE='/usr/local/lib/libnettle.so /usr/local/lib/libhogweed.so -lgmp -Wl,-rpath -Wl,/usr/local/lib'
   LTLIBNETTLE='-L/usr/local/lib -lnettle -L/usr/local/lib -lhogweed -lgmp -R/usr/local/lib'

but then  "make" will fail  because the old Nettle  does not
have the needed  functions ("nettle_umac_*", "nettle_ecc_*",
etc.); and after building fails I see:

   $ ldd lib/.libs/libgnutls.so
   linux-vdso.so.1 (0x00007fff1730b000)
   libz.so.1 => /usr/lib64/libz.so.1 (0x00007ff2c771d000)
   libp11-kit.so.0 => /usr/lib64/libp11-kit.so.0 (0x00007ff2c750b000)
   libtasn1.so.6 => /usr/local/lib/libtasn1.so.6 (0x00007ff2c72f8000)
   libnettle.so.4 => /usr/lib64/libnettle.so.4 (0x00007ff2c70d3000)
   libhogweed.so.2 => /usr/lib64/libhogweed.so.2 (0x00007ff2c6ec0000)
   libgmp.so.10 => /usr/lib64/libgmp.so.10 (0x00007ff2c6c54000)
   libc.so.6 => /lib64/libc.so.6 (0x00007ff2c6867000)
   libdl.so.2 => /lib64/libdl.so.2 (0x00007ff2c6662000)
   libpthread.so.0 => /lib64/libpthread.so.0 (0x00007ff2c6446000)
   /lib64/ld-linux-x86-64.so.2 (0x00007ff2c7c3a000)

so libtasn1 is correctly found but Nettle... I dunno.

  The same happens if I do:

   $ ./configure LDFLAGS=-L/usr/local/lib

  If I do:

   $ ./configure --with-libnettle-prefix=/usr/local
   ...
   checking whether to use nettle... yes
   checking for libnettle... no
   configure: error:
   ***
   *** Libnettle 2.7 was not found. Note that you must compile nettle with gmp support.

and:

   $ grep nettle config.log
   config.log:7: $ ./configure --with-libnettle-prefix=/usr/local
   config.log:595:configure:8886: checking whether to use nettle
   config.log:597:configure:9384: checking for libnettle
   config.log:598:configure:9406: gcc -std=gnu99 -o conftest -g -O2 conftest.c -lnettle -lhogweed -lgmp >&5
   config.log:600:/home/marco/var/build/lib/gnutls-3.2.0/conftest.c:35: undefined reference to `nettle_umac96_set_nonce'
   config.log:634:| #include <nettle/umac.h>
   config.log:638:| nettle_umac96_set_nonce (0,0,0)
   config.log:645: *** Libnettle 2.7 was not found. Note that you must compile nettle with gmp support.
   config.log:713:ac_cv_libnettle=no

and I see that "/usr/local/lib" is not used.

  It seems to me that the distributed "configure.ac" file is
not the one used to generate "configure"; is this weird?

  I need some help.

TIA
-- 
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