The --enable-libstdcxx-debug option builds extra versions of libstdc++
without optimisation and installs them in $libdir/debug, which can be
used via RPATH or LD_LIBRARY_PATH. However, there's no gdb.py
installed alongside those debug versions of the libs, so while you can
step into unoptimised libstdc++ code in GDB, you can't use the pretty
printers.
This patch installs a symlink in $libdir/debug pointing to the gdb.py
file in the parent dir, and adjusts the gdb.py file to handle the
$libdir/debug case. This seems to work. An alternative would be to
install a modified copy of the gdb.py file specific to that directory,
instead of a symlink to a file that works for either case.
Better ideas are welcome.
commit b4c640fed872eba973b6ca29326856b5a3101c39
Author: Jonathan Wakely <jwak...@redhat.com>
Date: Thu Jun 22 16:14:24 2017 +0100
possible fix
diff --git a/libstdc++-v3/python/Makefile.am b/libstdc++-v3/python/Makefile.am
index 80790e2..6090ffe 100644
--- a/libstdc++-v3/python/Makefile.am
+++ b/libstdc++-v3/python/Makefile.am
@@ -29,6 +29,12 @@ else
pythondir = $(datadir)/gcc-$(gcc_version)/python
endif
+if GLIBCXX_BUILD_DEBUG
+LINK_DEBUG = -$(LN_S) ../$$libname-gdb.py $(DESTDIR)$(toolexeclibdir)/debug/
+else
+LINK_DEBUG =
+endif
+
all-local: gdb.py
nobase_python_DATA = \
@@ -62,3 +68,5 @@ install-data-local: gdb.py
cd $$here; \
echo " $(INSTALL_DATA) gdb.py $(DESTDIR)$(toolexeclibdir)/$$libname-gdb.py"; \
$(INSTALL_DATA) gdb.py $(DESTDIR)$(toolexeclibdir)/$$libname-gdb.py
+ $(LINK_DEBUG)
+
diff --git a/libstdc++-v3/python/hook.in b/libstdc++-v3/python/hook.in
index b82604a6c..7701415 100644
--- a/libstdc++-v3/python/hook.in
+++ b/libstdc++-v3/python/hook.in
@@ -50,6 +50,8 @@ if gdb.current_objfile () is not None:
dotdots = ('..' + os.sep) * len (libdir.split (os.sep))
objfile = gdb.current_objfile ().filename
+ if str (os.path.dirname (objfile)).endswith (libdir + os.sep + "debug"):
+ dotdots = dotdots + ('..' + os.sep)
dir_ = os.path.join (os.path.dirname (objfile), dotdots, pythondir)
if not dir_ in sys.path:
