Add test for r32586.

FreeBSD (at least 7.2 to 7.2) calls nsdispatch(3) when it calls
getaddrinfo(3). And nsdispatch(3) doesn't call dlerror(3) even if
it calls _nss_cache_cycle_prevention_function with dlsym(3).
So our DL::Handle#sym must call dlerror(3) before call dlsym.
In general uses of dlerror(3) should call it before use it.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@32590 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 11 insertions, 0 deletions

diff --git a/test/dl/test_handle.rb b/test/dl/test_handle.rb
index 3f423925d9..cc4df49c84 100644
--- a/test/dl/test_handle.rb
+++ b/test/dl/test_handle.rb
@@ -169,5 +169,16 @@ module DL
       handle = DL::Handle::DEFAULT
       assert_not_nil handle['malloc']
     end unless /mswin|mingw/ =~ RUBY_PLATFORM
+
+    def test_dlerror
+      # FreeBSD (at least 7.2 to 7.2) calls nsdispatch(3) when it calls
+      # getaddrinfo(3). And nsdispatch(3) doesn't call dlerror(3) even if
+      # it calls _nss_cache_cycle_prevention_function with dlsym(3).
+      # So our DL::Handle#sym must call dlerror(3) before call dlsym.
+      # In general uses of dlerror(3) should call it before use it.
+      require 'socket'
+      Socket.gethostbyname("localhost")
+      DL.dlopen("/usr/lib/libc.so").sym('strcpy')
+    end if /freebsd/=~ RUBY_PLATFORM
   end
 end