Re: r147958 - in /trunk/libstdc++-v3: ChangeLog Mak...

[Tom Tromey <tromey at redhat dot com>]

>>>>> "Joseph" == Joseph S Myers <joseph@codesourcery.com> writes:

Joseph> I don't see a recent posting of this to gcc-patches (where all
Joseph> libstdc++ patches should be posted as well as the libstdc++
Joseph> list)

Sorry, I was unaware of this requirement.
I will remember in the future.

Joseph> - that is, an absolute, unrelocated path containing the
Joseph> configured prefix.  If the toolchain has been moved from the
Joseph> configured prefix (and for this I think you can assume GCC and
Joseph> GDB are moved together)

FWIW I don't think this assumption is warranted.

Joseph> I'm also concerned about the code that does
Joseph> libname=`cd $(toolexeclibdir) && ls -r libstdc++* | fgrep -v gdb.py | sed 1q`; \

Yeah, that does seem dubious.

Joseph> and while I'm not sure exactly what this code is trying to
Joseph> compute

The -gdb.py "hook" file must be named after the real name of the
objfile -- that is, after symlinks are resolved.  Finding this real
name is tricky because libtool hides it from us.


The appended patch attempts to address these issues, plus PR 40289:

* It changes the name of the python datadir to be versioned.
  I used "gcc" rather than "libstdc++" both because the gcc version
  number is more readily available, and because it leaves open the
  possibility of installing other gcc-specific pretty-printers.

* It now computes the new module path relative to the objfile.  This
  is better, in that moving the whole tree should work.  However, it
  assumes that datadir is always available as $libdir/../share.
  I'm not sure whether that is ok.

* It rewrites the install-data-local rule to use an explicit loop.
  I am still not extremely happy about this code, but I don't know
  what else to do.

Please review.

Tom

ChangeLog:
2009-05-29  Tom Tromey  <tromey@redhat.com>

	PR libstdc++/40289:
	* python/Makefile.in: Rebuild.
	* python/hook.in: Compute module path relative to objfile.
	* python/Makefile.am (pythondir): Redefine.
	(gdb.py): Subst gcc_version, not pythondir.
	(install-data-local): Rewrite.

Index: python/hook.in
===================================================================
--- python/hook.in	(revision 147958)
+++ python/hook.in	(working copy)
@@ -16,9 +16,14 @@
 
 import sys
 import gdb
+import os.path
 
-# Update module path.
-dir = '@dir@'
+# Update module path.  We assume that the library files are at a fixed
+# position relative to the objfile.
+datadir = 'gcc-@gcc_version@/python'
+objfile = gdb.current_objfile ().filename
+dir = os.path.join (os.path.dirname (objfile), '../share', datadir)
+
 if not dir in sys.path:
     sys.path.insert(0, dir)
 
Index: python/Makefile.am
===================================================================
--- python/Makefile.am	(revision 147958)
+++ python/Makefile.am	(working copy)
@@ -24,7 +24,7 @@
 include $(top_srcdir)/fragment.am
 
 ## Where to install the module code.
-pythondir = $(pkgdatadir)/python
+pythondir = $(datadir)/gcc-$(gcc_version)/python
 
 all-local: gdb.py
 
@@ -34,10 +34,26 @@
     libstdcxx/__init__.py
 
 gdb.py: hook.in Makefile
-	sed -e 's,@dir@,$(pythondir),' < $(srcdir)/hook.in > $@
+	sed -e 's,@gcc_version@,$(gcc_version),' < $(srcdir)/hook.in > $@
 
 install-data-local: gdb.py
 	@$(mkdir_p) $(DESTDIR)$(toolexeclibdir)
-	@libname=`cd $(toolexeclibdir) && ls -r libstdc++* | fgrep -v gdb.py | sed 1q`; \
+## We want to install gdb.py as SOMETHING-gdb.py.  SOMETHING is the
+## full name of the final library.  We want to ignore symlinks, the
+## .la file, and any previous -gdb.py file.  This is inherently
+## fragile, but there does not seem to be a better option, because
+## libtool hides the real names from us.
+	@here=`pwd`; cd $(toolexeclibdir); \
+	  for file in libstdc++*; do \
+	    case $$file in \
+	      *-gdb.py) ;; \
+	      *.la) ;; \
+	      *) if test -h $$file; then \
+	           continue; \
+	         fi; \
+	         libname=$$file;; \
+	    esac; \
+	  done; \
+	cd $$here; \
 	echo " $(INSTALL_DATA) gdb.py $(DESTDIR)$(toolexeclibdir)/$$libname-gdb.py"; \
 	$(INSTALL_DATA) gdb.py $(DESTDIR)$(toolexeclibdir)/$$libname-gdb.py