Discourage in-source autoconf builds (as we already do for the cmake build)

http://reviews.llvm.org/D7961

llvm-svn: 230812

1 files changed, 6 insertions, 0 deletions

diff --git a/llvm/configure b/llvm/configure
index cac9bf6533a..29437550f0d 100755
--- a/llvm/configure
+++ b/llvm/configure
@@ -1999,6 +1999,12 @@ echo "$as_me: error: Already configured in ${srcdir}" >&2;}
   fi
 fi
 
+if test ${srcdir} == "." ; then
+  { { echo "$as_me:$LINENO: error: In-source builds are discouraged. Configure from a separate build directory." >&5
+echo "$as_me: error: In-source builds are discouraged. Configure from a separate build directory." >&2;}
+   { (exit 1); exit 1; }; }
+fi
+
 : ${CFLAGS=}
 : ${CXXFLAGS=}