Today I ran into an issue when running a
bundle install on a project I've been working on for quite a while. Apparently MySQL does not play nice nowadays with Clang, Xcode's default compiler since 4.3.
An excerpt from my console:
> bundle install
Installing mysql2 (0.3.11)
Gem::Installer::ExtensionBuildError: ERROR: Failed to build gem native extension.
checking for rb_thread_blocking_region()... yes
checking for rb_wait_for_single_fd()... yes
checking for mysql.h... no
checking for mysql/mysql.h... no
mysql.h is missing. please check your installation of mysql and try again.
*** 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.
mkmf.log file we have the following error:
have_header: checking for mysqld_error.h... -------------------- yes
"gcc -E -I/Users/guido/.rbenv/versions/1.9.3-p392/include/ruby-1.9.1/x86_64-darwin12.3.0 -I/Users/guido/.rbenv/versions/1.9.3-p392/include/ruby-1.9.1/ruby/backward -I/Users/guido/.rbenv/versions/1.9.3-p392/include/ruby-1.9.1 -I. -I'/Users/guido/.rbenv/versions/1.9.3-p392/include' -D_XOPEN_SOURCE -D_DARWIN_C_SOURCE -I'/Users/guido/.rbenv/versions/1.9.3-p392/include' -I/usr/local/Cellar/mysql/5.6.12/include -Os -g -fno-strict-aliasing -Wno-error=shorten-64-to-32 -pipe conftest.c -o conftest.i"
checked program was:
/* begin */
1: #include "ruby.h"
3: #include <mysqld_error.h>
/* end */
Turns out that
mysql_config has some compile switches that work on GCC, but not on Clang. Lines 119 & 120 are the culprits, with the
cflags="-I$pkgincludedir -Wall -Wno-null-conversion -Wno-unused-private-field -Os -g -fno-strict-aliasing -DDBUG_OFF " #note: end space!
cxxflags="-I$pkgincludedir -Wall -Wno-null-conversion -Wno-unused-private-field -Os -g -fno-strict-aliasing -DDBUG_OFF " #note: end space!
Strip out the bad switches, and everything works fine:
cflags="-I$pkgincludedir -Wall -Os -g -fno-strict-aliasing -DDBUG_OFF " #note: end space!
cxxflags="-I$pkgincludedir -Wall -Os -g -fno-strict-aliasing -DDBUG_OFF " #note: end space!
mysql_config is situated in
/usr/local/mysql/bin/mysql_config. When using homebrew it's situated in
5.6.12 is your installed version of course.