diff --git a/CHANGELOG.md b/CHANGELOG.md
index 86c0127..437bd78 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -4,8 +4,16 @@
 
 ### Updates
 
+- GFE v1.21.0
+  - pFUnit v4.14.0
+    - Fixes for LLVM Flang among others
+
 ### Fixed
 
+- Added patches for FMS for llvm flang
+  - One for https://github.com/NOAA-GFDL/FMS/issues/1738
+  - One for https://github.com/NOAA-GFDL/FMS/issues/1739
+
 ### Changed
 
 ### Removed
diff --git a/GFE b/GFE
index 6f5586c..9be1379 160000
--- a/GFE
+++ b/GFE
@@ -1 +1 @@
-Subproject commit 6f5586c7a03a8689498f6f8dfa0573fe17b9ad03
+Subproject commit 9be13792f26ccab4076dba53d6c9d7a62c21d2ce
diff --git a/GNUmakefile b/GNUmakefile
index 4b54295..ed867c4 100644
--- a/GNUmakefile
+++ b/GNUmakefile
@@ -919,7 +919,16 @@ libyaml.config:
 		cmake -B build -S . -DCMAKE_INSTALL_PREFIX=$(prefix) -DCMAKE_PREFIX_PATH=$(prefix) -DCMAKE_POLICY_VERSION_MINIMUM=3.5 )
 	@touch $@
 
-FMS.config: netcdf.install netcdf-fortran.install libyaml.install
+# We need to patch FMS for LLVM
+#   https://github.com/NOAA-GFDL/FMS/issues/1739
+#   https://github.com/NOAA-GFDL/FMS/issues/1738
+# NOTE: Because we patch both source and CMake, we need to patch before
+# configuring and unpatch after installing
+FMS.config :: netcdf.install netcdf-fortran.install libyaml.install
+	@echo Patching FMS
+	patch -f -p1 < ./patches/FMS/llvm.patch
+
+FMS.config :: netcdf.install netcdf-fortran.install libyaml.install
 	@echo "Configuring FMS"
 	@mkdir -p ./FMS/build
 	@(cd ./FMS; \
@@ -1109,12 +1118,16 @@ libyaml.install: libyaml.config
 		cmake --build build --target install -j $(MAKEJOBS))
 	@touch $@
 
-FMS.install: FMS.config
+FMS.install :: FMS.config
 	@echo "Installing FMS"
 	@(cd ./FMS; \
 		cmake --build build --target install -j $(MAKEJOBS))
 	@touch $@
 
+FMS.install :: FMS.config
+	@echo Unpatching FMS
+	patch -f -p1 -R < ./patches/FMS/llvm.patch
+
 # MAT: Note that on Mac machines there seems to be an issue with the libtool setup
 #      in nco. If you just run nco, it never makes the libnco.a library, or at least
 #      does not make it correctly. As the nco/m4/libtool.m4 and, say, the
diff --git a/README.md b/README.md
index b6d5b42..7f562f5 100644
--- a/README.md
+++ b/README.md
@@ -19,7 +19,7 @@ NASA/GSFC.
 | [netCDF C++](https://github.com/Unidata/netcdf-cxx4)                     | 4.3.1        |
 | [HDF5](https://portal.hdfgroup.org/display/support)                      | 1.14.5       |
 | [HDF4](https://portal.hdfgroup.org/display/support)                      | 4.2.16-2     |
-| [GFE](https://github.com/Goddard-Fortran-Ecosystem/GFE)                  | v1.20.0      |
+| [GFE](https://github.com/Goddard-Fortran-Ecosystem/GFE)                  | v1.21.0      |
 | [xgboost](https://github.com/dmlc/xgboost)                               | v1.6.0       |
 | [libyaml](https://github.com/yaml/libyaml.git)                           | 0.2.5        |
 | [antlr2](https://www.antlr2.org/)                                        | 2.7.7        |
diff --git a/patches/FMS/llvm.patch b/patches/FMS/llvm.patch
new file mode 100644
index 0000000..b5b273b
--- /dev/null
+++ b/patches/FMS/llvm.patch
@@ -0,0 +1,32 @@
+--- a/FMS/mpp/include/mpp_chksum_int.fh
++++ b/FMS/mpp/include/mpp_chksum_int.fh
+@@ -53,8 +53,8 @@ function MPP_CHKSUM_INT_RMASK_( var, pelist, mask_val )
+   integer, optional :: pelist(:)
+   real, intent(in) :: mask_val
+   integer(KIND(var))::imask_val
+-  integer(KIND=i4_kind)::i4tmp(2)=0
+-  real(KIND=r4_kind)::r4tmp(2)=0
++  integer(KIND=i4_kind),allocatable::i4tmp(:)
++  real(KIND=r4_kind),allocatable::r4tmp(:)
+   integer(KIND=i8_kind) :: i8tmp=0
+   !high fidelity error message
+   character(LEN=1) :: tmpStr1,tmpStr2,tmpStr3
+--- a/FMS/CMakeLists.txt
++++ b/FMS/CMakeLists.txt
+@@ -325,6 +325,7 @@ foreach(kind ${kinds})
+                                                  mosaic2/include
+                                                  constants
+                                                  astronomy/include
++                                                 field_manager
+                                                  field_manager/include
+                                                  time_interp/include
+                                                  tracer_manager/include
+@@ -380,6 +381,7 @@ foreach(kind ${kinds})
+     $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/astronomy/include>
+     $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/monin_obukhov/include>
+     $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/sat_vapor_pres/include>
++    $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/field_manager>
+     $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/field_manager/include>
+     $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/horiz_interp/include>
+     $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/mosaic2/include>
+