diff --git a/.waf-tools/default-compiler-flags.py b/.waf-tools/default-compiler-flags.py
index bac1893..280165c 100644
--- a/.waf-tools/default-compiler-flags.py
+++ b/.waf-tools/default-compiler-flags.py
@@ -225,12 +225,13 @@
                 ['-isystem', f'{brewdir}/include'], # for Homebrew
                 ['-isystem', '/opt/local/include'], # for MacPorts
             ]
-        elif Utils.unversioned_sys_platform() == 'freebsd':
-            # Bug #4790
-            flags['CXXFLAGS'] += [['-isystem', '/usr/local/include']]
-        if get_compiler_ver(conf) >= (18, 0, 0) and get_compiler_ver(conf) < (20, 1, 0):
-            # Bug #5300
-            flags['CXXFLAGS'] += ['-Wno-enum-constexpr-conversion']
+        else:
+            if Utils.unversioned_sys_platform() == 'freebsd':
+                # Bug #4790
+                flags['CXXFLAGS'] += [['-isystem', '/usr/local/include']]
+            if get_compiler_ver(conf) >= (18, 0, 0) and get_compiler_ver(conf) < (20, 1, 0):
+                # Bug #5300
+                flags['CXXFLAGS'] += ['-Wno-enum-constexpr-conversion']
         return flags
 
     __cxxFlags = [
@@ -241,11 +242,13 @@
     def getDebugFlags(self, conf):
         flags = super().getDebugFlags(conf)
         flags['CXXFLAGS'] += self.__cxxFlags
+        ccver = get_compiler_ver(conf)
+        darwin = Utils.unversioned_sys_platform() == 'darwin'
         # Enable assertions in libc++
-        if get_compiler_ver(conf) >= (18, 0, 0):
+        if (darwin and ccver >= (17, 0, 0)) or (not darwin and ccver >= (18, 0, 0)):
             # https://libcxx.llvm.org/Hardening.html
             flags['DEFINES'] += ['_LIBCPP_HARDENING_MODE=_LIBCPP_HARDENING_MODE_EXTENSIVE']
-        elif get_compiler_ver(conf) >= (15, 0, 0):
+        elif ccver >= (15, 0, 0):
             # https://releases.llvm.org/15.0.0/projects/libcxx/docs/UsingLibcxx.html#enabling-the-safe-libc-mode
             flags['DEFINES'] += ['_LIBCPP_ENABLE_ASSERTIONS=1']
         # Tell libc++ to avoid including transitive headers
diff --git a/docs/doxygen.conf.in b/docs/doxygen.conf.in
index a956df4..2c9bb1e 100644
--- a/docs/doxygen.conf.in
+++ b/docs/doxygen.conf.in
@@ -1090,14 +1090,6 @@
 
 HTML_COLORSTYLE_GAMMA  = 91
 
-# If the HTML_TIMESTAMP tag is set to YES then the footer of each generated HTML
-# page will contain the date and time when the page was generated. Setting this
-# to NO can help when comparing the output of multiple runs.
-# The default value is: YES.
-# This tag requires that the tag GENERATE_HTML is set to YES.
-
-HTML_TIMESTAMP         = NO
-
 # If the HTML_DYNAMIC_SECTIONS tag is set to YES then the generated HTML
 # documentation will contain sections that can be hidden and shown after the
 # page has loaded.
@@ -1367,17 +1359,6 @@
 
 FORMULA_FONTSIZE       = 10
 
-# Use the FORMULA_TRANPARENT tag to determine whether or not the images
-# generated for formulas are transparent PNGs. Transparent PNGs are not
-# supported properly for IE 6.0, but are supported on all modern browsers.
-#
-# Note that when changing this option you need to delete any form_*.png files in
-# the HTML output directory before the changes have effect.
-# The default value is: YES.
-# This tag requires that the tag GENERATE_HTML is set to YES.
-
-FORMULA_TRANSPARENT    = YES
-
 # Enable the USE_MATHJAX option to render LaTeX formulas using MathJax (see
 # http://www.mathjax.org) which uses client side Javascript for the rendering
 # instead of using prerendered bitmaps. Use this if you do not have LaTeX
@@ -1975,15 +1956,6 @@
 # Configuration options related to the dot tool
 #---------------------------------------------------------------------------
 
-# If the CLASS_DIAGRAMS tag is set to YES doxygen will generate a class diagram
-# (in HTML and LaTeX) for classes with base or super classes. Setting the tag to
-# NO turns the diagrams off. Note that this option also works with HAVE_DOT
-# disabled, but it is recommended to install and use dot, since it yields more
-# powerful graphs.
-# The default value is: YES.
-
-CLASS_DIAGRAMS         = YES
-
 # If set to YES, the inheritance and collaboration graphs will hide inheritance
 # and usage relations if the target is undocumented or is not a class.
 # The default value is: YES.
@@ -2009,23 +1981,6 @@
 
 DOT_NUM_THREADS        = 0
 
-# When you want a differently looking font n the dot files that doxygen
-# generates you can specify the font name using DOT_FONTNAME. You need to make
-# sure dot is able to find the font, which can be done by putting it in a
-# standard location or by setting the DOTFONTPATH environment variable or by
-# setting DOT_FONTPATH to the directory containing the font.
-# The default value is: Helvetica.
-# This tag requires that the tag HAVE_DOT is set to YES.
-
-DOT_FONTNAME           = Helvetica
-
-# The DOT_FONTSIZE tag can be used to set the size (in points) of the font of
-# dot graphs.
-# Minimum value: 4, maximum value: 24, default value: 10.
-# This tag requires that the tag HAVE_DOT is set to YES.
-
-DOT_FONTSIZE           = 10
-
 # By default doxygen will tell dot to use the default font as specified with
 # DOT_FONTNAME. If you specify a different font using DOT_FONTNAME you can set
 # the path where dot can find it using this tag.
@@ -2208,18 +2163,6 @@
 
 MAX_DOT_GRAPH_DEPTH    = 0
 
-# Set the DOT_TRANSPARENT tag to YES to generate images with a transparent
-# background. This is disabled by default, because dot on Windows does not seem
-# to support this out of the box.
-#
-# Warning: Depending on the platform used, enabling this option may lead to
-# badly anti-aliased labels on the edges of a graph (i.e. they become hard to
-# read).
-# The default value is: NO.
-# This tag requires that the tag HAVE_DOT is set to YES.
-
-DOT_TRANSPARENT        = YES
-
 # Set the DOT_MULTI_TARGETS tag to YES allow dot to generate multiple output
 # files in one run (i.e. multiple -o and -T options on the command line). This
 # makes dot run faster, but since only newer versions of dot (>1.8.10) support