configure: Use same pattern to find headers for clang

diff --git a/configure b/configure
index 447318e678a29576275db98781d4754b54fe3844..4f7b42a319d557e2dca77613e6769792726666de 100755 (executable)
--- a/configure
+++ b/configure
@@ -5379,17 +5379,10 @@ fi
 if test -n "$CXX"; then
   # In theory the clang and gcc regexes can be merged, but the
   # result is incomprehensible.
-  if test "$with_clang" != no; then
-  find_cxx_header () {
-    echo "#include <$1>" | $CXX -M -MP -x c++ - 2>/dev/null \
-        | sed -n "\,^[o.-]*[ :] /.*/$1 [\]$,{s,^[o.-]*[ :] /,/,;s/ [\]$//;p}"
-  }
-  else
   find_cxx_header () {
     echo "#include <$1>" | $CXX -M -MP -x c++ - 2>/dev/null \
         | sed -n "\,$1:,{s/:\$//;p}"
   }
-  fi
   CXX_CSTDLIB_HEADER="$(find_cxx_header cstdlib)"
   CXX_CMATH_HEADER="$(find_cxx_header cmath)"
   CXX_BITS_STD_ABS_H="$(find_cxx_header bits/std_abs.h)"