]> https://gitweb.dealii.org/ - dealii-svn.git/commitdiff
Add the Makefile which generates the forward declarations file.
authorwolf <wolf@0785d39b-7218-0410-832d-ea1e28bc413d>
Wed, 24 Feb 1999 13:38:34 +0000 (13:38 +0000)
committerwolf <wolf@0785d39b-7218-0410-832d-ea1e28bc413d>
Wed, 24 Feb 1999 13:38:34 +0000 (13:38 +0000)
git-svn-id: https://svn.dealii.org/trunk@897 0785d39b-7218-0410-832d-ea1e28bc413d

deal.II/deal.II/Make.forward-declarations [new file with mode: 0644]

diff --git a/deal.II/deal.II/Make.forward-declarations b/deal.II/deal.II/Make.forward-declarations
new file mode 100644 (file)
index 0000000..225b335
--- /dev/null
@@ -0,0 +1,42 @@
+# rule how to make the file containing all the forward declarations
+# taken from the deal.II Makefile
+#
+# this rule is rather complicated, it works as follows:
+#
+# - if this is the outermost 'make', then create a file $@.old.
+#   if the forward declaration file $@ already exists, then copy
+#   it over, otherwise leave it empty. this way, we always have
+#   a file to run diff on
+# - write the forward declarations for the presently available
+#   header files to $@.new
+# - we would like to compare the output of the script generating
+#   the forward declarations with the old file, or the empty
+#   string if there is no such file; this is why we created $@.old
+# - if the files differ, we would like to copy over the old file.
+# - this can either be done using shell programming using 'if [...]'
+#   or using conditionals inside 'make'. the first way is not 
+#   portable over different shells, however, and I also do not know
+#   how to write it. the second way has a problem also: conditionals
+#   are evaluated at the time the Makefile is read first, so we
+#   can't compare against $@.old, since this file does not exist at
+#   that time.
+# - we therefore invoke a second 'make', which can compare the two
+#   files against each other in a preconditional clause and
+#   copy over the file if necessary.
+# - delete the two temporary files
+$(forward-declarations): $(filter-out $(forward-declarations),$(h-files))
+ifeq (0,${MAKELEVEL})
+       @echo ============================ Checking $@
+       @touch $@.old
+       -@cp $@ $@.old
+       @perl $D/deal.II/Make_forward_declarations $(filter-out $(forward-declarations),$(h-files)) > $@.new
+       @make --silent $@
+       @rm $@.old $@.new
+else
+  ifneq (,$(shell diff $(forward-declarations).old $(forward-declarations).new))
+       @echo ============================ Generating $@
+       @cp $@.new $@
+  else
+       @echo "============================          $@ needs no change"
+  endif
+endif

In the beginning the Universe was created. This has made a lot of people very angry and has been widely regarded as a bad move.

Douglas Adams


Typeset in Trocchi and Trocchi Bold Sans Serif.