Build: Version dependency for python modules (issue 1726).

[lilypond.git] / stepmake / stepmake / help2man-rules.make

diff --git a/stepmake/stepmake/help2man-rules.make b/stepmake/stepmake/help2man-rules.make
index ee9f13e32ded9a2f9b3f6e74f78507a21d2baa9a..6c176bac5e7b0995cf33ee66ed452cb4e2bc802a 100644 (file)
--- a/stepmake/stepmake/help2man-rules.make
+++ b/stepmake/stepmake/help2man-rules.make
@@ -1,9 +1,42 @@
-# ugh. 
-# Man-page:
+# We must invoke the generated $(outdir)/help2man script instead of
+# the help2man.pl source, which means that the scripts/build directory
+# must be built first.
+#
+# From the perlrun man-page:
+#
 #      If the #! line does not contain the word "perl", the
 #       program named after the #! is executed instead of the Perl
 #       interpreter.  This is slightly bizarre, but it helps
-# Indeed it is. Perl sucks.
 #
-$(outdir)/%.1: $(outdir)/%
-       $(PERL) $(depth)/buildscripts/$(outdir)/help2man $< > $@
+# Indeed it is.  Perl sucks.
+#
+# Two screenfulls explaining that the otherwise standard #! is broken
+# for perl, and arguing that this broken magic is better in some
+# cases.  Four more explaining what a line comment is, and that it may
+# be parsed, same here.
+
+ifeq ($(PYTHON),$(TARGET_PYTHON))
+HELP2MAN_COMMAND = $(buildscript-dir)/help2man $< > $@
+else
+HELP2MAN_COMMAND = $(buildscript-dir)/help2man "env $$(basename $$(head -1 $<)) $<" > $@
+endif
+
+ifeq ($(strip $(CROSS)),no)
+$(outdir)/%.1: $(outdir)/% $(buildscript-dir)/help2man
+       $(HELP2MAN_COMMAND)
+else
+# When cross building, some manpages will not build because the
+# executable does not run.  We assume the manpages to be generated
+# during a previous compile for the build host, with config=for-build,
+# in the directory $(outdir)-for-build.
+$(outdir)/%.1: $(outdir:%=%-for-build)/%.1
+       cp $< $@
+endif
+
+ifneq ($(outdir),./out)
+$(outdir)/%.1: out/%.1
+       cp $< $@
+endif
+
+$(buildscript-dir)/help2man:
+       $(MAKE) -C $(depth)/scripts/build