diff --git a/guitarix2-0.42.1-gcc-11.0.patch b/guitarix2-0.42.1-gcc-11.0.patch
new file mode 100644
index 0000000..345f5e9
--- /dev/null
+++ b/guitarix2-0.42.1-gcc-11.0.patch
@@ -0,0 +1,13 @@
+diff --git a/src/headers/gx_system.h b/src/headers/gx_system.h
+index d334ecfc..88d97567 100644
+--- a/src/headers/gx_system.h
++++ b/src/headers/gx_system.h
+@@ -132,7 +132,7 @@ inline T *atomic_get(T*& p) {
+ 
+ template <class T>
+ inline bool atomic_compare_and_exchange(T **p, T *oldv, T *newv) {
+-    return g_atomic_pointer_compare_and_exchange(reinterpret_cast<void* volatile*>(p), static_cast<void*>(oldv), newv);
++    return g_atomic_pointer_compare_and_exchange(reinterpret_cast<void**>(p), static_cast<void*>(oldv), newv);
+ }
+ 
+ 
diff --git a/guitarix2.spec b/guitarix2.spec
index a6979ce..1dd5517 100644
--- a/guitarix2.spec
+++ b/guitarix2.spec
@@ -1,49 +1,56 @@
 Name:          guitarix2
-Version:       0.34.0
+Version:       0.42.1
 Release:       1mamba
 Summary:       A simple mono amplifier to be used in a 'JACKified' environment
 Group:         Graphical Desktop/Applications/Multimedia
 Vendor:        openmamba
 Distribution:  openmamba
 Packager:      Silvan Calarco <silvan.calarco@mambasoft.it>
-URL:           http://guitarix.sourceforge.net/
-Source:        http://downloads.sourceforge.net/project/guitarix/guitarix/guitarix2-%{version}.tar.bz2
+URL:           https://guitarix.sourceforge.net/
+Source:        http://downloads.sourceforge.net/project/guitarix/guitarix/guitarix2-%{version}.tar.xz
+Patch0:        guitarix2-0.42.1-gcc-11.0.patch
 License:       GPL
 ## AUTOBUILDREQ-BEGIN
 BuildRequires: glibc-devel
+BuildRequires: libX11-devel
 BuildRequires: libatk-devel
-BuildRequires: libatkmm-devel
+BuildRequires: libatkmm1-devel
 BuildRequires: libavahi-devel
 BuildRequires: libavahi-glib-devel
 BuildRequires: libbluetooth-devel
 BuildRequires: libboost-devel
 BuildRequires: libcairo-devel
-BuildRequires: libcairomm-devel
+BuildRequires: libcairomm10-devel
+BuildRequires: libcurl-devel
 BuildRequires: libfftw-devel
-BuildRequires: libfontconfig-devel
-BuildRequires: libfreetype-devel
 BuildRequires: libgcc
 BuildRequires: libgdk-pixbuf-devel
 BuildRequires: libglib-devel
-BuildRequires: libglibmm-devel
-BuildRequires: libgtk2-devel
-BuildRequires: libgtkmm2-devel
+BuildRequires: libglibmm24-devel
+BuildRequires: libgtk3-devel
+BuildRequires: libgtkmm3-devel
+BuildRequires: libharfbuzz-devel
 BuildRequires: libjack-devel
 BuildRequires: liblilv-devel
+BuildRequires: liblo-devel
 BuildRequires: liblrdf-devel
 BuildRequires: libpango-devel
-BuildRequires: libpangomm-devel
+BuildRequires: libpangomm1-devel
 BuildRequires: libserd-devel
-BuildRequires: libsigc++-devel
+BuildRequires: libsigc++2-devel
 BuildRequires: libsndfile-devel
 BuildRequires: libsord-devel
 BuildRequires: libsratom-devel
 BuildRequires: libstdc++6-devel
+BuildRequires: libzita-convolver-devel
+BuildRequires: libzita-resampler-devel
 ## AUTOBUILDREQ-END
 BuildRequires: eigen3-devel
+BuildRequires: libgtkmm3-devel
+BuildRequires: libzita-resampler-devel
+BuildRequires: faust
 Requires:      lib%{name} = %{?epoch:%epoch:}%{version}-%{release}
 Provides:      guitarix
-BuildRoot:     %{_tmppath}/%{name}-%{version}-root
 
 %description
 Guitarix is a simple mono amplifier to be used in a 'JACKified' environment, i.e. a system using the JACK Audio Connection Kit, a professionally-capable audio/MIDI server and master transport control
@@ -59,8 +66,6 @@ This package contains shared libraries for %{name}.
 Group:         Development/Libraries
 Summary:       Development files for %{name}
 Requires:      lib%{name} = %{?epoch:%epoch:}%{version}-%{release}
-## note: you can add this requirement if .pc files are provided by this package
-#Requires:      pkg-config
 
 %description -n lib%{name}-devel
 This package contains libraries and header files for developing applications that use %{name}.
@@ -70,6 +75,7 @@ This package contains libraries and header files for developing applications tha
 
 %prep
 %setup -q -n guitarix-%{version}
+%patch0 -p1
 
 %build
 ./waf configure \
@@ -109,15 +115,15 @@ This package contains libraries and header files for developing applications tha
 %{_datadir}/gx_head/sounds/bands/*.wav
 %{_datadir}/gx_head/sounds/bands/LICENSE
 %{_datadir}/gx_head/sounds/greathall.wav
-%{_datadir}/ladspa/rdf/guitarix.rdf
-%{_datadir}/ladspa/rdf/guitarix_amp.rdf
+#%{_datadir}/ladspa/rdf/guitarix.rdf
+#%{_datadir}/ladspa/rdf/guitarix_amp.rdf
 %{_datadir}/pixmaps/*.png
 %doc COPYING
 
 %files -n lib%{name}
 %defattr(-,root,root)
-%{_libdir}/ladspa/guitarix*.so
-%{_libdir}/ladspa/ladspa_guitarix.so
+#%{_libdir}/ladspa/guitarix*.so
+#%{_libdir}/ladspa/ladspa_guitarix.so
 %{_libdir}/libgxw.so
 %{_libdir}/libgxw.so.*
 %{_libdir}/libgxwmm.so
@@ -129,6 +135,9 @@ This package contains libraries and header files for developing applications tha
 #%doc README README.developers
 
 %changelog
+* Tue May 11 2021 Silvan Calarco <silvan.calarco@mambasoft.it> 0.42.1-1mamba
+- update to 0.42.1
+
 * Fri Jan 01 2016 Automatic Build System <autodist@mambasoft.it> 0.34.0-1mamba
 - automatic version update by autodist