diff --git a/pythia8.spec b/pythia8.spec
index 51d40e956dd..c6500fc95f4 100644
--- a/pythia8.spec
+++ b/pythia8.spec
@@ -1,11 +1,14 @@
 ### RPM external pythia8 309
 
 Source: https://pythia.org/download/pythia83/%{n}%{realversion}.tgz
+# https://gitlab.com/Pythia8/releases/-/issues/289: fix compilation of C++20 code with pythia8
+Patch0: pythia8_309-289
 
 Requires: hepmc hepmc3 lhapdf
 
 %prep
 %setup -q -n %{n}%{realversion}
+%patch0 -p1
 
 ./configure --prefix=%i --enable-shared --with-hepmc2=${HEPMC_ROOT} --with-hepmc3=${HEPMC3_ROOT} --with-lhapdf6=${LHAPDF_ROOT} --enable-mg5mes
 
diff --git a/pythia8_309-289.patch b/pythia8_309-289.patch
new file mode 100644
index 00000000000..ec5ba6655bc
--- /dev/null
+++ b/pythia8_309-289.patch
@@ -0,0 +1,31 @@
+diff --git a/include/Pythia8/SusyLesHouches.h b/include/Pythia8/SusyLesHouches.h
+index 43d6d621..5a57a968 100644
+--- a/include/Pythia8/SusyLesHouches.h
++++ b/include/Pythia8/SusyLesHouches.h
+@@ -28,7 +28,7 @@ namespace Pythia8 {
+   public:
+ 
+     //Constructor.
+-    LHblock<T>() : idnow(0), qDRbar(), i(), val() {} ;
++    LHblock() : idnow(0), qDRbar(), i(), val() {} ;
+ 
+     //Does block exist?
+     bool exists() { return int(entry.size()) == 0 ? false : true ; };
+@@ -129,7 +129,7 @@ namespace Pythia8 {
+   template <int size> class LHmatrixBlock {
+   public:
+     //Constructor. Set uninitialized and explicitly zero.
+-    LHmatrixBlock<size>() : entry(), qDRbar(), val() {
++    LHmatrixBlock() : entry(), qDRbar(), val() {
+       initialized=false;
+       for (i=1;i<=size;i++) {
+         for (j=1;j<=size;j++) {
+@@ -208,7 +208,7 @@ namespace Pythia8 {
+   template <int size> class LHtensor3Block {
+   public:
+     //Constructor. Set uninitialized and explicitly zero.
+-    LHtensor3Block<size>() : entry(), qDRbar(), val() {
++    LHtensor3Block() : entry(), qDRbar(), val() {
+       initialized=false;
+       for (i=1;i<=size;i++) {
+         for (j=1;j<=size;j++) {
diff --git a/sherpa-cpp20.patch b/sherpa-cpp20.patch
new file mode 100644
index 00000000000..b76c3ace7a5
--- /dev/null
+++ b/sherpa-cpp20.patch
@@ -0,0 +1,35 @@
+From 1de52ee230891277370fc4f787fc8cb4b7626ef2 Mon Sep 17 00:00:00 2001
+From: iarspider <iarspider@gmail.com>
+Date: Wed, 28 Jun 2023 07:35:10 +0000
+Subject: [PATCH] [ATOOLS] Fix C++20 compilation errors
+
+---
+ ATOOLS/Org/Getter_Function.H | 5 ++---
+ 1 file changed, 2 insertions(+), 3 deletions(-)
+
+diff --git a/ATOOLS/Org/Getter_Function.H b/ATOOLS/Org/Getter_Function.H
+index f68d190ca2..09340da390 100644
+--- a/ATOOLS/Org/Getter_Function.H
++++ b/ATOOLS/Org/Getter_Function.H
+@@ -84,7 +84,7 @@ namespace ATOOLS {
+       void PrintInfo(std::ostream &str,const size_t width) const;	\
+       Object_Type *operator()(const Parameter_Type &parameters) const;	\
+     public:								\
+-      Getter<OBJECT,PARAMETER,NAME,SORT>(const bool &d=true):		\
++      Getter(const bool &d=true):		\
+ 	Getter_Function<OBJECT,PARAMETER,SORT>(TAG)			\
+ 	{ SetDisplay(d); }						\
+     };									\
+@@ -107,8 +107,7 @@ namespace ATOOLS {
+       void PrintInfo(std::ostream &str,const size_t width) const;	\
+       Object_Type *operator()(const Parameter_Type &parameters) const;	\
+     public:								\
+-      Getter<OBJECT,PARAMETER,NAME,SORT>				\
+-	(const std::string &name,const bool d=true):			\
++      Getter(const std::string &name,const bool d=true):			\
+ 	Getter_Function<OBJECT,PARAMETER,SORT>(name)			\
+ 	{ SetDisplay(d); }						\
+     };									\
+-- 
+GitLab
+
diff --git a/sherpa.spec b/sherpa.spec
index 31ad30dad9b..5809ddd88df 100644
--- a/sherpa.spec
+++ b/sherpa.spec
@@ -3,6 +3,7 @@ Source: http://www.hepforge.org/archive/sherpa/SHERPA-MC-%{realversion}.tar.gz
 Requires: hepmc lhapdf blackhat sqlite python3 fastjet openmpi
 BuildRequires: mcfm swig autotools
 Patch0: sherpa-2.2.10-hepmcshort
+Patch1: sherpa-cpp20
 
 %ifos linux
 %ifnarch ppc64le
@@ -25,6 +26,7 @@ perl -p -i -e 's|-rdynamic||g' configure AddOns/Analysis/Scripts/Makefile.in
 %endif
 
 %patch0 -p1
+%patch1 -p1
 
 %build
 export PYTHON=$(which python3)
diff --git a/tensorflow-sources.file b/tensorflow-sources.file
index e21ee248f79..853ec1ff5b1 100644
--- a/tensorflow-sources.file
+++ b/tensorflow-sources.file
@@ -5,6 +5,12 @@ BuildRequires: bazel java-env git
 ## INCLUDE tensorflow-requires
 ## INCLUDE compilation_flags
 
+#Set cms_cxx_standard to 17 as LLVM downloaded by TF does not build with c++20
+%if "%{cms_cxx_standard}" == "20"
+%undefine cms_cxx_standard
+%define cms_cxx_standard 17
+%endif
+
 Source: git+https://github.com/%{github_user}/tensorflow.git?obj=%{branch}/%{tag}&export=tensorflow-%{realversion}&output=/tensorflow-%{realversion}.tgz
 
 %if "%{?build_type:set}" != "set"