Merged revisions 78817 via svnmerge from

svn+ssh://pythondev@svn.python.org/python/trunk

........
  r78817 | benjamin.peterson | 2010-03-09 15:43:36 -0600 (Tue, 09 Mar 2010) | 1 line

  handle an empty OPT variable correctly #8100
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configure

@@ -4521,7 +4521,7 @@ fi
 # tweak OPT based on compiler and platform, only if the user didn't set
 # it on the command line
 
-if test -z "$OPT"
+if test "${OPT-unset}" == "unset"
 then
     case $GCC in
     yes)

configure.in

@@ -819,7 +819,7 @@ fi],
 # tweak OPT based on compiler and platform, only if the user didn't set
 # it on the command line
 AC_SUBST(OPT)
-if test -z "$OPT"
+if test "${OPT-unset}" == "unset"
 then
     case $GCC in
     yes)