Close #13415: Test in configure if unsetenv() has a return value or not.

Patch written by Charles-François Natali.

1 files changed, 28 insertions, 0 deletions

diff --git a/configure b/configure
index 596336ee96..112c20aa6f 100755
--- a/configure
+++ b/configure
@@ -9812,6 +9812,34 @@ $as_echo "no" >&6; }
 fi
 rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
 
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for broken unsetenv" >&5
+$as_echo_n "checking for broken unsetenv... " >&6; }
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
+#include <stdlib.h>
+
+int
+main ()
+{
+int res = unsetenv("DUMMY")
+  ;
+  return 0;
+}
+_ACEOF
+if ac_fn_c_try_compile "$LINENO"; then :
+  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
+$as_echo "no" >&6; }
+else
+
+$as_echo "#define HAVE_BROKEN_UNSETENV 1" >>confdefs.h
+
+   { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+$as_echo "yes" >&6; }
+
+fi
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+
 for ac_prog in true
 do
   # Extract the first word of "$ac_prog", so it can be a program name with args.