Merge issue #15819: additional fixes for out-of-tree builds from read-only src.

Specifically, make sure the 'Object', 'Python' and 'Include' directories
in the build directory take precedence over the source directory if we're
an out-of-tree build.

Fix typeslots.inc so that it gets generated into the build directory.

In addition, for 3.3, make sure importlib.h gets generated into the
build directory.

1 files changed, 20 insertions, 0 deletions

diff --git a/configure b/configure
index 31fc3d6..843b141 100755
--- a/configure
+++ b/configure
@@ -714,6 +714,8 @@ HAS_HG
 HGBRANCH
 HGTAG
 HGVERSION
+BASECPPFLAGS
+BUILDDIR
 target_alias
 host_alias
 build_alias
@@ -2719,6 +2721,24 @@ ac_compiler_gnu=$ac_cv_c_compiler_gnu
 
 
 
+BUILDDIR="`pwd`"
+
+
+if test "$srcdir" != "$BUILDDIR"; then
+    # If we're building out-of-tree, we need to make sure the following
+    # resources get picked up before their $srcdir counterparts.
+    #   Objects/ -> typeslots.inc
+    #   Include/ -> Python-ast.h, graminit.h
+    #   Python/  -> importlib.h
+    # (A side effect of this is that these resources will automatically be
+    #  regenerated when building out-of-tree, regardless of whether or not
+    #  the $srcdir counterpart is up-to-date.  This is an acceptable trade
+    #  off.)
+    BASECPPFLAGS="-IObjects -IInclude -IPython"
+else
+    BASECPPFLAGS=""
+fi
+