configure: clang: explicitly state dep file and rule name in DEPFLAGS

Fixes dependency file generation with gas-preprocessor.pl and clang.
Flags copied from GCC and tested with Apple's clang from Xcode 5 and
5.1 and clang 3.2, 3.3, 3.4 on Linux.

diff --git a/configure b/configure
index b7ff79c1c1f5a05d14d2e02929130535aa72d8fb..81a4c7ae270bc4b2ab3d91a3c9dc09bce0db1ff2 100755 (executable)
--- a/configure
+++ b/configure
@@ -2702,7 +2702,7 @@ probe_cc(){
     elif $_cc -v 2>&1 | grep -q clang; then
         _type=clang
         _ident=$($_cc --version | head -n1)
-        _depflags='-MMD'
+        _depflags='-MMD -MF $(@:.o=.d) -MT $@'
         _cflags_speed='-O3'
         _cflags_size='-Os'
     elif $_cc -V 2>&1 | grep -q Sun; then