[gcc r13-7267] libstdc++: Strip absolute paths from files shown in Doxygen docs

[Jonathan Wakely <redi@gcc.gnu.org>]

https://gcc.gnu.org/g:bf9e62a9210d3d7756a6cf81607bb3ea80c5f8f7

commit r13-7267-gbf9e62a9210d3d7756a6cf81607bb3ea80c5f8f7
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Fri Apr 28 11:22:26 2023 +0100

    libstdc++: Strip absolute paths from files shown in Doxygen docs
    
    This avoids showing absolute paths from the expansion of
    @srcdir@/libsupc++/ in the doxygen File List view.
    
    libstdc++-v3/ChangeLog:
    
            * doc/doxygen/user.cfg.in (STRIP_FROM_PATH): Remove prefixes
            from header paths.
    
    (cherry picked from commit 975e8e836ead0e9055a125a2a23463db5d847cb3)

Diff:
---
 libstdc++-v3/doc/doxygen/user.cfg.in | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/libstdc++-v3/doc/doxygen/user.cfg.in b/libstdc++-v3/doc/doxygen/user.cfg.in
index 9d814af8614..ed260520690 100644
--- a/libstdc++-v3/doc/doxygen/user.cfg.in
+++ b/libstdc++-v3/doc/doxygen/user.cfg.in
@@ -152,7 +152,7 @@ FULL_PATH_NAMES        = NO
 # will be relative from the directory where doxygen is started.
 # This tag requires that the tag FULL_PATH_NAMES is set to YES.
 
-STRIP_FROM_PATH        =
+STRIP_FROM_PATH        = @srcdir@/doc/ @srcdir@/libsupc++/ include/
 
 # The STRIP_FROM_INC_PATH tag can be used to strip a user-defined part of the
 # path mentioned in the documentation of a class, which tells the reader which
@@ -837,6 +837,7 @@ WARN_LOGFILE           =
 # spaces. See also FILE_PATTERNS and EXTENSION_MAPPING
 # Note: If this tag is empty the current directory is searched.
 
+# N.B. update STRIP_FROM_PATH to sanitize paths outside the build tree.
 INPUT                  = @srcdir@/doc/doxygen/doxygroups.cc \
                          @srcdir@/libsupc++/compare \
                          @srcdir@/libsupc++/cxxabi.h \