Comment 1 Steve Wills 2017-07-08 02:12:44 UTC

There are a number of things going on here. The libelf warning is just that, a warning. It doesn't cause an error. The real issue is as you say the requirement on pkg-config 1.1.x. That was fixed in r445195, so I think this issue is solved now. Please let me know if you still have an issue.

As a side note, there's another issue with nokogiri where it will build with -Werror and die due to a bug in ruby:

"cc -I/usr/local/include/ruby-2.4//amd64-freebsd12 -I/usr/local/include/ruby-2.4//ruby/backward -I/usr/local/include/ruby-2.4/ -I. -I/usr/local/include -isystem /usr/local/include   -O2 -pipe  -fstack-protector -isystem /usr/local/include -fno-strict-aliasing -fPIC    -Werror -c conftest.c"
In file included from conftest.c:1:
In file included from /usr/local/include/ruby-2.4/ruby.h:33:
/usr/local/include/ruby-2.4/ruby/ruby.h:915:1: error: attribute '__deprecated__' is ignored, place it after "struct" to apply attribute to type declaration [-Werror,-Wignored-attributes]
DEPRECATED_TYPE(("RClass is internal use only"),
^
/usr/local/include/ruby-2.4//amd64-freebsd12/ruby/config.h:126:49: note: expanded from macro 'DEPRECATED_TYPE'
#define DEPRECATED_TYPE(mesg,x) __attribute__ ((__deprecated__ mesg)) x
                                                ^
In file included from conftest.c:1:
In file included from /usr/local/include/ruby-2.4/ruby.h:33:
/usr/local/include/ruby-2.4/ruby/ruby.h:2152:1: error: unknown attribute '__error__' ignored [-Werror,-Wunknown-attributes]
ERRORFUNC(("bad scan arg format"), int rb_scan_args_bad_format(const char*));
^
/usr/local/include/ruby-2.4//amd64-freebsd12/ruby/config.h:131:43: note: expanded from macro 'ERRORFUNC'
#define ERRORFUNC(mesg,x) __attribute__ ((__error__ mesg)) x
                                          ^
In file included from conftest.c:1:
In file included from /usr/local/include/ruby-2.4/ruby.h:33:
/usr/local/include/ruby-2.4/ruby/ruby.h:2153:1: error: unknown attribute '__error__' ignored [-Werror,-Wunknown-attributes]
ERRORFUNC(("variable argument length doesn't match"), int rb_scan_args_length_mismatch(const char*,int));
^
/usr/local/include/ruby-2.4//amd64-freebsd12/ruby/config.h:131:43: note: expanded from macro 'ERRORFUNC'
#define ERRORFUNC(mesg,x) __attribute__ ((__error__ mesg)) x
                                          ^
3 errors generated.
checked program was:
/* begin */
1: #include "ruby.h"
2:
3: int main() {return 0;}
/* end */

But this is only in the case where you try to build nokogiri without the --use-system-libraries flags and is really a bug in nokogiri for passing the -Werror flag, and a bug in ruby for bad use of C macros.

(In reply to Steve Wills from comment #1)
> There are a number of things going on here. The libelf warning is just
> that, a warning. It doesn't cause an error.

It did cause error when using pkg_config function in mkmf. You can test it by creating a wrapper script called 'cc' and put it in PATH,

#!/bin/sh
echo 'warning: Hello World!' 1>&2
exec /usr/bin/cc "$@"

and write a simple program printing the result of pkg_config call.

require 'mkmf'
require 'pp'
pp pkg_config 'zlib'

You will see 'nil' because of the warning message. The content of mkmf.log:

"pkg-config --exists zlib"
| pkg-config --libs zlib
=> "-lz \n"
"cc -o conftest -I/usr/local/include/ruby-2.3//amd64-freebsd11 -I/usr/local/include/ruby-2.3//ruby/backward -I/usr/local/include/ruby-2.3/ -I. -I/usr/local/include -isystem /usr/local/include   -O2 -pipe -march=sandybridge  -fstack-protector -isystem /usr/local/include -fno-strict-aliasing -fPIC conftest.c  -L. -L/usr/local/lib -L.   -fstack-protector -rdynamic     -lruby23  -lelf -lunwind -lexecinfo -lprocstat -lcrypt -lm -lpthread -L/usr/local/lib -L/usr/local/lib  -lc"
warning: Hello World!
checked program was:
/* begin */
1: #include "ruby.h"
2: 
3: int main(int argc, char **argv)
4: {
5:   return 0;
6: }
/* end */

"cc -o conftest -I/usr/local/include/ruby-2.3//amd64-freebsd11 -I/usr/local/include/ruby-2.3//ruby/backward -I/usr/local/include/ruby-2.3/ -I. -I/usr/local/include -isystem /usr/local/include   -O2 -pipe -march=sandybridge  -fstack-protector -isystem /usr/local/include -fno-strict-aliasing -fPIC conftest.c  -L. -L/usr/local/lib -L.   -fstack-protector -rdynamic     -lruby23 -lz -lelf -lunwind -lexecinfo -lprocstat -lcrypt -lm -lpthread -L/usr/local/lib -L/usr/local/lib  -lc"
warning: Hello World!
checked program was:
/* begin */
1: #include "ruby.h"
2: 
3: int main(int argc, char **argv)
4: {
5:   return 0;
6: }
/* end */

package configuration for zlib is not found

> The real issue is as you say the requirement on pkg-config 1.1.x.

If the pkg_config check didn't fail, it would not use rubygem-pkg-config. This is why it can be built in poudriere without patching the version requirement of rubygem-pkg-config.

> That was fixed in r445195, so I think this issue is solved now.
> Please let me know if you still have an issue.

Yes, it is fixed now.