gistfile1

diff --git a/third_party/generic/pypy/pypy/rpython/module/ll_os.py b/third_party/generic/pypy/pypy/rpython/module/ll_os.py
index ebcccf7..e7d02a1 100644
--- a/third_party/generic/pypy/pypy/rpython/module/ll_os.py
+++ b/third_party/generic/pypy/pypy/rpython/module/ll_os.py
@@ -88,10 +88,31 @@ class RegisterOs(BaseLazyRegistering):
     def __init__(self):
         self.configure(CConfig)
 
+        # on some platforms, e.g. OS X Leopard, the following constants which
+        # may be defined in pyconfig.h triggers "legacy" behaviour for functions
+        # like setpgrp():
+        #
+        #   _POSIX_C_SOURCE 200112L
+        #   _XOPEN_SOURCE 600
+        #   _DARWIN_C_SOURCE 1
+        #
+        # since the translation currently includes pyconfig.h, the checkcompiles
+        # call below include the pyconfig.h file so that the same behaviour is
+        # present in both the check and the final translation...
+
         if hasattr(os, 'getpgrp'):
-            self.GETPGRP_HAVE_ARG = platform.checkcompiles("getpgrp(0)", "#include <unistd.h>")
+            self.GETPGRP_HAVE_ARG = platform.checkcompiles(
+                "getpgrp(0)",
+                '#include "pyconfig.h"\n#include <unistd.h>',
+                [platform.get_python_include_dir()]
+                )
+
         if hasattr(os, 'setpgrp'):
-            self.SETPGRP_HAVE_ARG = platform.checkcompiles("setpgrp(0,0)", "#include <unistd.h>")
+            self.SETPGRP_HAVE_ARG = platform.checkcompiles(
+                "setpgrp(0,0)",
+                '#include "pyconfig.h"\n#include <unistd.h>',
+                [platform.get_python_include_dir()]
+                )
 
         # we need an indirection via c functions to get macro calls working on llvm XXX still?
         if hasattr(os, 'WCOREDUMP'):
diff --git a/third_party/generic/pypy/pypy/rpython/tool/rffi_platform.py b/third_party/generic/pypy/pypy/rpython/tool/rffi_platform.py
index 3c383e4..aa4620a 100755
--- a/third_party/generic/pypy/pypy/rpython/tool/rffi_platform.py
+++ b/third_party/generic/pypy/pypy/rpython/tool/rffi_platform.py
@@ -14,9 +14,10 @@ import distutils
 #
 # Helpers for simple cases
 
-def eci_from_header(c_header_source):
+def eci_from_header(c_header_source, include_dirs=[]):
     return ExternalCompilationInfo(
-        pre_include_bits=[c_header_source]
+        pre_include_bits=[c_header_source],
+        include_dirs=include_dirs
     )
 
 def getstruct(name, c_header_source, interesting_fields):
@@ -43,9 +44,9 @@ def getdefined(macro, c_header_source):
         DEFINED = Defined(macro)
     return configure(CConfig)['DEFINED']
 
-def has(name, c_header_source):
+def has(name, c_header_source, include_dirs=[]):
     class CConfig:
-        _compilation_info_ = eci_from_header(c_header_source)
+        _compilation_info_ = eci_from_header(c_header_source, include_dirs)
         HAS = Has(name)
     return configure(CConfig)['HAS']
 
@@ -57,9 +58,9 @@ def verify_eci(eci):
         WORKS = Works()
     configure(CConfig)
     
-def checkcompiles(expression, c_header_source):
+def checkcompiles(expression, c_header_source, include_dirs=[]):
     """Check if expression compiles. If not, returns False"""
-    return has(expression, c_header_source)
+    return has(expression, c_header_source, include_dirs)
     
 def sizeof(name, eci, **kwds):
     class CConfig: