Error compiling on Ruby 1.8.7

[postmodern]

g++ -I. -I. -I/opt/rubies/ruby-1.8.7-p371/lib/ruby/1.8/x86_64-linux -I. -DHAVE_RUBY_ENCODING_H    -fPIC -g -O2    -c unf.cc
In file included from unf.cc:5:0:
/usr/include/ruby/encoding.h:101:68: error: expected identifier before numeric constant
/usr/include/ruby/encoding.h:101:68: error: expected ‘,’ or ‘...’ before numeric constant
/usr/include/ruby/encoding.h:101:73: error: expected constructor, destructor, or type conversion before ‘;’ token
In file included from unf.cc:5:0:
/usr/include/ruby/encoding.h:213:65: error: declaration of C function ‘long int rb_memsearch(const void*, long int, const void*, long int, rb_encoding*)’ conflicts with
In file included from /opt/rubies/ruby-1.8.7-p371/lib/ruby/1.8/x86_64-linux/ruby.h:756:0,
                 from unf.cc:3:
/opt/rubies/ruby-1.8.7-p371/lib/ruby/1.8/x86_64-linux/intern.h:387:6: error: previous declaration ‘long int rb_memsearch(const void*, long int, const void*, long int)’ here
make: *** [unf.o] Error 1

It does successfully build on Ruby 1.9.3. I would be OK if unf_ext set gemspec.required_ruby_version to >= 1.9.1.

[knu]

Having /usr/include/ruby/encoding.h is unusual and it seems something is seriously broken with your installation.
Ruby's header files should be placed inside each version specific directory and must not be globally exposed.

[knu]

Solution: Just remove /usr/include/ruby/. If it was installed by some package, ask the vendor to fix it.

[knu]

Maybe there are also /usr/include/ruby.h and /usr/lib/libruby*, which may as well be moved away.

[postmodern]

Ah ha! I have ruby 1.8.7 installed into /opt/rubies/ruby-1.8.7-p371. For some reason extconf isn't finding it's headers, but instead using system's ruby headers.

[postmodern]

Ah there is no encoding.h in /opt/rubies/ruby-1.8.7-p371/lib/ruby/1.8/x86_64-linux/.

[knu]

ruby/encoding.h was introduced in ruby 1.9.

And ruby never installs its header files directly under /usr/include unless wrongly configured.

[postmodern]

It appears have_header('ruby/encoding.h') in ext/unf/extconf.rb is causing -DHAVE_RUBY_ENCODING_H to be passed in, and thus ruby/encoding.h get's included in. You should probably also check the version of Ruby, since ruby/encoding.h should never be included for Ruby 1.8.x.

[knu]

This is a bug of the ruby-devel rpm. I'll bug report the issue when I feel like it.
There are many other modules that do have_header("ruby/...") in their extconf.rb, so it doesn't help if I only "fix" my module.

[postmodern]

Confirmed. I renamed /usr/include/ruby to /usr/include/ruby-1.9.1 and the module compiled.

[knu]

Just filed a bug report: https://bugzilla.redhat.com/show_bug.cgi?id=245446

Thanks for the report. I wouldn't notice the issue if it weren't for this.

[knu]

The URL I posted above was a wrong one. Follow this instead: https://bugzilla.redhat.com/show_bug.cgi?id=975660