* depend2.am (%.o): Handle deleted header file problem.

	(%.lo): Likewise.

diff --git a/ChangeLog b/ChangeLog
index 9c8c1ce..5dfbc93 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,8 @@
 Thu Oct  1 00:51:51 1998  Tom Tromey  <tromey@cygnus.com>
 
+       * depend2.am (%.o): Handle deleted header file problem.
+       (%.lo): Likewise.
+
        * texinfos.am (install-info-am): Handle case where INFO_DEPS is
        empty.  Reported by Andrew Cagney.
        (uninstall-info): Likewise.

diff --git a/NEWS b/NEWS
index 3dd3bb1..d9d1d2e 100644 (file)
--- a/NEWS
+++ b/NEWS
@@ -4,6 +4,7 @@ New in 1.3b:
 * Support for latest autoconf, including support for objext
 * Can now put `.' in SUBDIRS to control build order
 * `include' command
+* Dependency tracking no long susceptible to deleted header file problem
 * Bug fixes
 \f
 New in 1.3:

diff --git a/depend2.am b/depend2.am
index 09cb938..7e4c6a3 100644 (file)
--- a/depend2.am
+++ b/depend2.am
@@ -26,12 +26,30 @@
 ##   -MM, not -M (despite what the docs say).
 ## - Using -M directly means running the compiler twice (even worse
 ##   than renaming).
-       $(@PFX@COMPILE) -Wp,-MD,.deps/$(*F).P -c $<
+       $(@PFX@COMPILE) -Wp,-MD,.deps/$(*F).p -c $<
+## This next piece of magic avoids the `deleted header file' problem.
+## The problem is that when a header file which appears in a .P file
+## is deleted, the dependency causes make to die (because there is
+## typically no way to rebuild the header).  We avoid this by adding
+## dummy dependencies for each header file.  Too bad gcc doesn't do
+## this for us directly.
+       @-tr '\\ ' '\n\n' < .deps/$(*F).p \
+## The very first nondeleted line is always the primary source file.
+## No need for that, so we remove it too via `1d'.
+         | sed -e '/^$$/ d' -e '/:$$/ d' -e 1d -e 's/$$/:/' > .deps/$(*F).P; \
+       rm .deps/$(*F).p
 
 %.lo: %@EXT@
        @echo '$(LT@PFX@COMPILE) -c $<'; \
 ## See above to understand implementation weirdness.
        $(LT@PFX@COMPILE) -Wp,-MD,.deps/$(*F).p -c $<
        @-sed -e 's/^\([^:]*\)\.o:/\1.lo \1.o:/' \
-         < .deps/$(*F).p > .deps/$(*F).P
-       @-rm -f .deps/$(*F).p
+         < .deps/$(*F).p > .deps/$(*F).P; \
+## See above to understand deleted header file trick.
+       tr '\\ ' '\n\n' < .deps/$(*F).p \
+## The very first nondeleted line is always the primary source file.
+## No need for that, so we remove it too via `1d'.
+         | sed -e '/^$$/ d' -e '/:$$/ d' -e 1d -e 's/$$/:/' \
+## Note subtle difference: here we append to the .P file.
+           >> .deps/$(*F).P; \
+       rm -f .deps/$(*F).p

diff --git a/lib/am/depend2.am b/lib/am/depend2.am
index 09cb938..7e4c6a3 100644 (file)
--- a/lib/am/depend2.am
+++ b/lib/am/depend2.am
@@ -26,12 +26,30 @@
 ##   -MM, not -M (despite what the docs say).
 ## - Using -M directly means running the compiler twice (even worse
 ##   than renaming).
-       $(@PFX@COMPILE) -Wp,-MD,.deps/$(*F).P -c $<
+       $(@PFX@COMPILE) -Wp,-MD,.deps/$(*F).p -c $<
+## This next piece of magic avoids the `deleted header file' problem.
+## The problem is that when a header file which appears in a .P file
+## is deleted, the dependency causes make to die (because there is
+## typically no way to rebuild the header).  We avoid this by adding
+## dummy dependencies for each header file.  Too bad gcc doesn't do
+## this for us directly.
+       @-tr '\\ ' '\n\n' < .deps/$(*F).p \
+## The very first nondeleted line is always the primary source file.
+## No need for that, so we remove it too via `1d'.
+         | sed -e '/^$$/ d' -e '/:$$/ d' -e 1d -e 's/$$/:/' > .deps/$(*F).P; \
+       rm .deps/$(*F).p
 
 %.lo: %@EXT@
        @echo '$(LT@PFX@COMPILE) -c $<'; \
 ## See above to understand implementation weirdness.
        $(LT@PFX@COMPILE) -Wp,-MD,.deps/$(*F).p -c $<
        @-sed -e 's/^\([^:]*\)\.o:/\1.lo \1.o:/' \
-         < .deps/$(*F).p > .deps/$(*F).P
-       @-rm -f .deps/$(*F).p
+         < .deps/$(*F).p > .deps/$(*F).P; \
+## See above to understand deleted header file trick.
+       tr '\\ ' '\n\n' < .deps/$(*F).p \
+## The very first nondeleted line is always the primary source file.
+## No need for that, so we remove it too via `1d'.
+         | sed -e '/^$$/ d' -e '/:$$/ d' -e 1d -e 's/$$/:/' \
+## Note subtle difference: here we append to the .P file.
+           >> .deps/$(*F).P; \
+       rm -f .deps/$(*F).p