I've tried many solutions but nothing seems to work! I use Ruby 1.9.3 and Rails 3.1.3 and I want to install the ruby-debug19 gem. This ist what I get from the PowerShell:
PS C:\Users\**\**\**> gem install ruby-debug19
Temporarily enhancing PATH to include DevKit...
Building native extensions. This could take a while...
ERROR: Error installing ruby-debug19:
ERROR: Failed to build gem native extension.
C:/Ruby193/bin/ruby.exe extconf.rb
checking for rb_method_entry_t.body in method.h... no
checking for vm_core.h... no
C:/Ruby193/lib/ruby/gems/1.9.1/gems/ruby_core_source-0.1.5/lib/ruby_core_source.rb:39: Use RbConfig instead of obsolete and deprecated Config.
checking for rb_method_entry_t.body in method.h... no
checking for vm_core.h... yes
checking for iseq.h... yes
checking for insns.inc... yes
checking for insns_info.inc... yes
checking for eval_intern.h... yes
creating Makefile
make
generating ruby_debug-i386-mingw32.def
compiling breakpoint.c
compiling ruby_debug.c
ruby_debug.c:29:19: error: conflicting types for 'rb_iseq_compile_with_option'
C:/Ruby193/include/ruby-1.9.1/ruby-1.9.3-p0/vm_core.h:505:7: note: previous declaration of 'rb_iseq_compile_with_option' was here
ruby_debug.c: In function 'context_jump':
ruby_debug.c:2414:53: warning: comparison between signed and unsigned integer expressions
ruby_debug.c:2428:27: warning: comparison between signed and unsigned integer expressions
make: *** [ruby_debug.o] Error 1
Gem files will remain installed in C:/Ruby193/lib/ruby/gems/1.9.1/gems/ruby-debug-base19-0.11.25 for inspection.
Results logged to C:/Ruby193/lib/ruby/gems/1.9.1/gems/ruby-debug-base19-0.11.25/ext/ruby_debug/gem_make.out