Installation on CygWin: Can't find the PostgreSQL client library (libpq)

[larskanis]

Original report by Jacek Tomaszewski (Bitbucket: jacektomaszewski, GitHub: jacektomaszewski).

---

I use Windows 8 x64 and CygWin. The message is following:

#!txt

$ gem install pg
Building native extensions.  This could take a while...
ERROR:  Error installing pg:
        ERROR: Failed to build gem native extension.

        /usr/bin/ruby.exe extconf.rb
checking for pg_config... yes
Using config values from /usr/bin/pg_config
checking for libpq-fe.h... yes
checking for libpq/libpq-fs.h... yes
checking for pg_config_manual.h... yes
checking for PQconnectdb() in -lpq... no
checking for PQconnectdb() in -llibpq... no
checking for PQconnectdb() in -lms/libpq... no
Can't find the PostgreSQL client library (libpq)
*** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of
necessary libraries and/or headers.  Check the mkmf.log file for more
details.  You may need configuration options.

Provided configuration options:
        --with-opt-dir
        --without-opt-dir
        --with-opt-include
        --without-opt-include=${opt-dir}/include
        --with-opt-lib
        --without-opt-lib=${opt-dir}/lib
        --with-make-prog
        --without-make-prog
        --srcdir=.
        --curdir
        --ruby=/usr/bin/ruby
        --with-pg
        --without-pg
        --with-pg-dir
        --without-pg-dir
        --with-pg-include
        --without-pg-include=${pg-dir}/include
        --with-pg-lib
        --without-pg-lib=${pg-dir}/lib
        --with-pg-config
        --without-pg-config
        --with-pg_config
        --without-pg_config
        --with-pqlib
        --without-pqlib
        --with-libpqlib
        --without-libpqlib
        --with-ms/libpqlib
        --without-ms/libpqlib

Gem files will remain installed in /usr/lib/ruby/gems/1.9.1/gems/pg-0.15.1 for inspect                                                                                  ion.
Results logged to /usr/lib/ruby/gems/1.9.1/gems/pg-0.15.1/ext/gem_make.out

I've got installed postgresql, libpq5, libpq-devel by cygwin. The paths seem okay: as the log says, pq_config and libpq-fe.h are being loaded.

I have search through whole the internet and I can't find anyone with similiar issue. There are some solutions with using config path directives like 'with-pq-config=...' but it's not helping in my case.

I've tried installing older versions of pg but the newest one I can install is pg-0.9.0 .

Any guesses what causes this problem and how to fix it? I can't develop our teams' ruby project on my PC and still want to stay on Windows =S

[larskanis]

Original comment by Jacek Tomaszewski (Bitbucket: jacektomaszewski, GitHub: jacektomaszewski).

---

[larskanis]

Original comment by Jacek Tomaszewski (Bitbucket: jacektomaszewski, GitHub: jacektomaszewski).

---

I must be dumber than I expected..

$ gem install pg -v 0.15.1 --platform="x86-mingw32" solved the issue.

[larskanis]

Original comment by Lars Kanis (Bitbucket: larskanis, GitHub: larskanis).

---

--platform=x86-mingw32 installs a precompiled binary gem that is targeted to mingw like the OneClickInstaller and doesn't have any dependencies. I wonder that it works on cygwin - I thought that cygwin isn't binary compatible to mingw.

Nevertheless, could you copy and paste you mkmf.log from the installation directory of the source gem? It usually allows proper diagnosis of the issue.

[larskanis]

Original comment by Jacek Tomaszewski (Bitbucket: jacektomaszewski, GitHub: jacektomaszewski).

---

Here's the mkmf.log :

#!log

find_executable: checking for pg_config... -------------------- yes

--------------------

find_header: checking for libpq-fe.h... -------------------- yes

"gcc -o conftest -I/usr/include/ruby-1.9.1/i386-cygwin -I/usr/include/ruby-1.9.1/ruby/backward -I/usr/include/ruby-1.9.1 -I.    -I/usr/include -ggdb -O2 -pipe   -fno-strict-aliasing conftest.c  -L. -L/usr/lib -L.  -L/usr/lib -Wl,-rpath,/usr/lib     -lruby191  -lpthread -lrt -ldl -lcrypt  "
checked program was:
/* begin */
1: #include "ruby.h"
2: 
3: int main() {return 0;}
/* end */

"gcc -E -I/usr/include/ruby-1.9.1/i386-cygwin -I/usr/include/ruby-1.9.1/ruby/backward -I/usr/include/ruby-1.9.1 -I.    -I/usr/include -ggdb -O2 -pipe   -fno-strict-aliasing  conftest.c -o conftest.i"
checked program was:
/* begin */
1: #include "ruby.h"
2: 
3: #include <libpq-fe.h>
/* end */

--------------------

find_header: checking for libpq/libpq-fs.h... -------------------- yes

"gcc -E -I/usr/include/ruby-1.9.1/i386-cygwin -I/usr/include/ruby-1.9.1/ruby/backward -I/usr/include/ruby-1.9.1 -I.    -I/usr/include -ggdb -O2 -pipe   -fno-strict-aliasing  conftest.c -o conftest.i"
checked program was:
/* begin */
1: #include "ruby.h"
2: 
3: #include <libpq/libpq-fs.h>
/* end */

--------------------

find_header: checking for pg_config_manual.h... -------------------- yes

"gcc -E -I/usr/include/ruby-1.9.1/i386-cygwin -I/usr/include/ruby-1.9.1/ruby/backward -I/usr/include/ruby-1.9.1 -I.    -I/usr/include -ggdb -O2 -pipe   -fno-strict-aliasing  conftest.c -o conftest.i"
checked program was:
/* begin */
1: #include "ruby.h"
2: 
3: #include <pg_config_manual.h>
/* end */

--------------------

have_library: checking for PQconnectdb() in -lpq... -------------------- no

"gcc -o conftest -I/usr/include/ruby-1.9.1/i386-cygwin -I/usr/include/ruby-1.9.1/ruby/backward -I/usr/include/ruby-1.9.1 -I.    -I/usr/include -ggdb -O2 -pipe   -fno-strict-aliasing conftest.c  -L. -L/usr/lib -L.  -L/usr/lib -Wl,-rpath,/usr/lib     -lruby191 -lpq  -lpthread -lrt -ldl -lcrypt  "
/usr/lib/libpq.a(fe-connect.o): In function `ldapServiceLookup':
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-connect.c:3541: undefined reference to `_ldap_init'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-connect.c:3553: undefined reference to `_ldap_simple_bind'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-connect.c:3563: undefined reference to `_ldap_result'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-connect.c:3576: undefined reference to `_ldap_msgfree'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-connect.c:3580: undefined reference to `_ldap_search_st'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-connect.c:3584: undefined reference to `_ldap_msgfree'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-connect.c:3585: undefined reference to `_ldap_err2string'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-connect.c:3588: undefined reference to `_ldap_unbind'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-connect.c:3594: undefined reference to `_ldap_count_entries'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-connect.c:3622: undefined reference to `_ldap_msgfree'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-connect.c:3623: undefined reference to `_ldap_unbind'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-connect.c:3569: undefined reference to `_ldap_msgfree'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-connect.c:3573: undefined reference to `_ldap_unbind'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-connect.c:3606: undefined reference to `_ldap_first_entry'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-connect.c:3618: undefined reference to `_ldap_get_values_len'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-connect.c:3628: undefined reference to `_ldap_msgfree'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-connect.c:3648: undefined reference to `_ldap_value_free_len'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-connect.c:3649: undefined reference to `_ldap_unbind'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-connect.c:3661: undefined reference to `_ldap_value_free_len'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-connect.c:3662: undefined reference to `_ldap_unbind'
/usr/lib/libpq.a(fe-misc.o): In function `libpq_gettext':
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-misc.c:1202: undefined reference to `_libintl_bindtextdomain'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-misc.c:1210: undefined reference to `_libintl_dgettext'
/usr/lib/libpq.a(fe-misc.o): In function `pqSocketCheck':
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-misc.c:1025: undefined reference to `_SSL_pending'
/usr/lib/libpq.a(fe-secure.o): In function `SSLerrmessage':
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:1512: undefined reference to `_ERR_get_error'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:1518: undefined reference to `_ERR_reason_error_string'
/usr/lib/libpq.a(fe-secure.o): In function `initialize_SSL':
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:1094: undefined reference to `_SSL_CTX_use_certificate_chain_file'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:1104: undefined reference to `_SSL_use_certificate_file'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:1140: undefined reference to `_ENGINE_by_id'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:1153: undefined reference to `_ENGINE_init'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:1167: undefined reference to `_ENGINE_load_private_key'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:1183: undefined reference to `_SSL_use_PrivateKey'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:1253: undefined reference to `_SSL_check_private_key'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:1281: undefined reference to `_SSL_CTX_load_verify_locations'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:1292: undefined reference to `_SSL_CTX_get_cert_store'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:1322: undefined reference to `_SSL_set_verify'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:1239: undefined reference to `_SSL_use_PrivateKey_file'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:1357: undefined reference to `_SSL_ctrl'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:1303: undefined reference to `_X509_STORE_load_locations'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:1307: undefined reference to `_X509_STORE_set_flags'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:1177: undefined reference to `_ENGINE_finish'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:1178: undefined reference to `_ENGINE_free'
/usr/lib/libpq.a(fe-secure.o): In function `init_ssl_system':
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:946: undefined reference to `_TLSv1_method'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:946: undefined reference to `_SSL_CTX_new'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:965: undefined reference to `_SSL_CTX_ctrl'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:929: undefined reference to `_CRYPTO_set_id_callback'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:930: undefined reference to `_CRYPTO_set_locking_callback'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:940: undefined reference to `_OPENSSL_config'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:942: undefined reference to `_SSL_library_init'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:943: undefined reference to `_SSL_load_error_strings'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:908: undefined reference to `_CRYPTO_num_locks'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:914: undefined reference to `_CRYPTO_num_locks'
/usr/lib/libpq.a(fe-secure.o): In function `destroySSL':
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:999: undefined reference to `_CRYPTO_set_locking_callback'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:1000: undefined reference to `_CRYPTO_set_id_callback'
/usr/lib/libpq.a(fe-secure.o): In function `pqsecure_write':
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:490: undefined reference to `_SSL_write'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:491: undefined reference to `_SSL_get_error'
/usr/lib/libpq.a(fe-secure.o): In function `pqsecure_read':
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:329: undefined reference to `_SSL_read'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:330: undefined reference to `_SSL_get_error'
/usr/lib/libpq.a(fe-secure.o): In function `close_SSL':
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:1466: undefined reference to `_SSL_shutdown'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:1467: undefined reference to `_SSL_free'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:1477: undefined reference to `_X509_free'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:1484: undefined reference to `_ENGINE_finish'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:1485: undefined reference to `_ENGINE_free'
/usr/lib/libpq.a(fe-secure.o): In function `open_client_SSL':
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:1378: undefined reference to `_SSL_connect'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:1432: undefined reference to `_SSL_get_peer_certificate'
/usr/lib/libpq.a(fe-secure.o): In function `verify_peer_name_matches_certificate':
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:756: undefined reference to `_X509_get_subject_name'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:756: undefined reference to `_X509_NAME_get_text_by_NID'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:772: undefined reference to `_X509_get_subject_name'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:772: undefined reference to `_X509_NAME_get_text_by_NID'
/usr/lib/libpq.a(fe-secure.o): In function `open_client_SSL':
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:1381: undefined reference to `_SSL_get_error'
/usr/lib/libpq.a(fe-secure.o): In function `pqsecure_open_client':
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:258: undefined reference to `_SSL_new'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:259: undefined reference to `_SSL_set_ex_data'
/pub/devel/postgresql/postgresql-9.2.4-1/src/postgresql-9.2.4/src/interfaces/libpq/fe-secure.c:260: undefined reference to `_SSL_set_fd'
/usr/lib/libpq.a(chklocale.o): In function `pg_get_encoding_from_locale':
/pub/devel/postgresql/postgresql-9.2.4-1/build/src/interfaces/libpq/chklocale.c:269: undefined reference to `_libintl_setlocale'
/pub/devel/postgresql/postgresql-9.2.4-1/build/src/interfaces/libpq/chklocale.c:277: undefined reference to `_libintl_setlocale'
/pub/devel/postgresql/postgresql-9.2.4-1/build/src/interfaces/libpq/chklocale.c:292: undefined reference to `_libintl_setlocale'
/pub/devel/postgresql/postgresql-9.2.4-1/build/src/interfaces/libpq/chklocale.c:298: undefined reference to `_libintl_setlocale'
/pub/devel/postgresql/postgresql-9.2.4-1/build/src/interfaces/libpq/chklocale.c:351: undefined reference to `_libintl_gettext'
collect2: ld returned 1 exit status
checked program was:
/* begin */
1: #include "ruby.h"
2: 
3: #include <libpq-fe.h>
4: 
5: /*top*/
6: int main() {return 0;}
7: int t() { void ((*volatile p)()); p = (void ((*)()))PQconnectdb; return 0; }
/* end */

"gcc -o conftest -I/usr/include/ruby-1.9.1/i386-cygwin -I/usr/include/ruby-1.9.1/ruby/backward -I/usr/include/ruby-1.9.1 -I.    -I/usr/include -ggdb -O2 -pipe   -fno-strict-aliasing conftest.c  -L. -L/usr/lib -L.  -L/usr/lib -Wl,-rpath,/usr/lib     -lruby191 -lpq  -lpthread -lrt -ldl -lcrypt  "
conftest.c: In function ‘t’:
conftest.c:7:1: error: too few arguments to function ‘PQconnectdb’
/usr/include/libpq-fe.h:245:16: note: declared here
checked program was:
/* begin */
1: #include "ruby.h"
2: 
3: #include <libpq-fe.h>
4: 
5: /*top*/
6: int main() {return 0;}
7: int t() { PQconnectdb(); return 0; }
/* end */

--------------------

have_library: checking for PQconnectdb() in -llibpq... -------------------- no

"gcc -o conftest -I/usr/include/ruby-1.9.1/i386-cygwin -I/usr/include/ruby-1.9.1/ruby/backward -I/usr/include/ruby-1.9.1 -I.    -I/usr/include -ggdb -O2 -pipe   -fno-strict-aliasing conftest.c  -L. -L/usr/lib -L.  -L/usr/lib -Wl,-rpath,/usr/lib     -lruby191 -llibpq  -lpthread -lrt -ldl -lcrypt  "
/usr/lib/gcc/i686-pc-cygwin/4.5.3/../../../../i686-pc-cygwin/bin/ld: cannot find -llibpq
collect2: ld returned 1 exit status
checked program was:
/* begin */
1: #include "ruby.h"
2: 
3: #include <libpq-fe.h>
4: 
5: /*top*/
6: int main() {return 0;}
7: int t() { void ((*volatile p)()); p = (void ((*)()))PQconnectdb; return 0; }
/* end */

"gcc -o conftest -I/usr/include/ruby-1.9.1/i386-cygwin -I/usr/include/ruby-1.9.1/ruby/backward -I/usr/include/ruby-1.9.1 -I.    -I/usr/include -ggdb -O2 -pipe   -fno-strict-aliasing conftest.c  -L. -L/usr/lib -L.  -L/usr/lib -Wl,-rpath,/usr/lib     -lruby191 -llibpq  -lpthread -lrt -ldl -lcrypt  "
conftest.c: In function ‘t’:
conftest.c:7:1: error: too few arguments to function ‘PQconnectdb’
/usr/include/libpq-fe.h:245:16: note: declared here
checked program was:
/* begin */
1: #include "ruby.h"
2: 
3: #include <libpq-fe.h>
4: 
5: /*top*/
6: int main() {return 0;}
7: int t() { PQconnectdb(); return 0; }
/* end */

--------------------

have_library: checking for PQconnectdb() in -lms/libpq... -------------------- no

"gcc -o conftest -I/usr/include/ruby-1.9.1/i386-cygwin -I/usr/include/ruby-1.9.1/ruby/backward -I/usr/include/ruby-1.9.1 -I.    -I/usr/include -ggdb -O2 -pipe   -fno-strict-aliasing conftest.c  -L. -L/usr/lib -L.  -L/usr/lib -Wl,-rpath,/usr/lib     -lruby191 -lms/libpq  -lpthread -lrt -ldl -lcrypt  "
/usr/lib/gcc/i686-pc-cygwin/4.5.3/../../../../i686-pc-cygwin/bin/ld: cannot find -lms/libpq
collect2: ld returned 1 exit status
checked program was:
/* begin */
1: #include "ruby.h"
2: 
3: #include <libpq-fe.h>
4: 
5: /*top*/
6: int main() {return 0;}
7: int t() { void ((*volatile p)()); p = (void ((*)()))PQconnectdb; return 0; }
/* end */

"gcc -o conftest -I/usr/include/ruby-1.9.1/i386-cygwin -I/usr/include/ruby-1.9.1/ruby/backward -I/usr/include/ruby-1.9.1 -I.    -I/usr/include -ggdb -O2 -pipe   -fno-strict-aliasing conftest.c  -L. -L/usr/lib -L.  -L/usr/lib -Wl,-rpath,/usr/lib     -lruby191 -lms/libpq  -lpthread -lrt -ldl -lcrypt  "
conftest.c: In function ‘t’:
conftest.c:7:1: error: too few arguments to function ‘PQconnectdb’
/usr/include/libpq-fe.h:245:16: note: declared here
checked program was:
/* begin */
1: #include "ruby.h"
2: 
3: #include <libpq-fe.h>
4: 
5: /*top*/
6: int main() {return 0;}
7: int t() { PQconnectdb(); return 0; }
/* end */

--------------------

[larskanis]

Original comment by Jacek Tomaszewski (Bitbucket: jacektomaszewski, GitHub: jacektomaszewski).

---

larskanis is right and this didn't solve the issue - mingw compiler works only with RubyInstaller on Windows, which is IMHO much worse than CygWin enviroment.

Still looking forward to fix this bug - It's currently the last ruby library I have problems to install with on cygwin.

[larskanis]

Original comment by Lars Kanis (Bitbucket: larskanis, GitHub: larskanis).

---

I wonder why dependencies to OpenSSL, LDAP and libintl are not resolved automatically. Obviously the linker options -lcrypto -lldap -lintl are needed. Maybe something like set LDFLAGS=-lcrypto -lldap -lintl does the trick. Unfortunately none of the maintainers of ruby-pg is using CygWin, so we probably can not help promptly.

[larskanis]

Original comment by Lars Kanis (Bitbucket: larskanis, GitHub: larskanis).

---

No response anymore, so I'll close the issue for now. Please reopen if the issue still remains.