diff -Naur cmake-3.18.2.orig/Modules/Compiler/Absoft-Fortran.cmake cmake-3.18.2/Modules/Compiler/Absoft-Fortran.cmake
--- cmake-3.18.2.orig/Modules/Compiler/Absoft-Fortran.cmake	2020-09-08 13:30:51.134086928 +0000
+++ cmake-3.18.2/Modules/Compiler/Absoft-Fortran.cmake	2020-09-10 08:44:13.788373968 +0000
@@ -1,7 +1,7 @@
 string(APPEND CMAKE_Fortran_FLAGS_INIT " ")
 string(APPEND CMAKE_Fortran_FLAGS_DEBUG_INIT " -g")
 string(APPEND CMAKE_Fortran_FLAGS_MINSIZEREL_INIT " ")
-string(APPEND CMAKE_Fortran_FLAGS_RELEASE_INIT " -O3")
+string(APPEND CMAKE_Fortran_FLAGS_RELEASE_INIT " -O2")
 string(APPEND CMAKE_Fortran_FLAGS_RELWITHDEBINFO_INIT " -O2 -g")
 set(CMAKE_Fortran_MODDIR_FLAG "-YMOD_OUT_DIR=")
 set(CMAKE_Fortran_MODPATH_FLAG "-p")
diff -Naur cmake-3.18.2.orig/Modules/Compiler/G95-Fortran.cmake cmake-3.18.2/Modules/Compiler/G95-Fortran.cmake
--- cmake-3.18.2.orig/Modules/Compiler/G95-Fortran.cmake	2020-09-08 13:30:51.136086957 +0000
+++ cmake-3.18.2/Modules/Compiler/G95-Fortran.cmake	2020-09-10 08:44:22.991490916 +0000
@@ -1,7 +1,7 @@
 string(APPEND CMAKE_Fortran_FLAGS_INIT " ")
 string(APPEND CMAKE_Fortran_FLAGS_DEBUG_INIT " -g")
 string(APPEND CMAKE_Fortran_FLAGS_MINSIZEREL_INIT " -Os")
-string(APPEND CMAKE_Fortran_FLAGS_RELEASE_INIT " -O3")
+string(APPEND CMAKE_Fortran_FLAGS_RELEASE_INIT " -O2")
 string(APPEND CMAKE_Fortran_FLAGS_RELWITHDEBINFO_INIT " -O2 -g")
 set(CMAKE_Fortran_MODDIR_FLAG "-fmod=")
 set(CMAKE_Fortran_VERBOSE_FLAG "-v")
diff -Naur cmake-3.18.2.orig/Modules/Compiler/GNU-Fortran.cmake cmake-3.18.2/Modules/Compiler/GNU-Fortran.cmake
--- cmake-3.18.2.orig/Modules/Compiler/GNU-Fortran.cmake	2020-09-08 13:30:51.137086972 +0000
+++ cmake-3.18.2/Modules/Compiler/GNU-Fortran.cmake	2020-09-10 08:44:10.635333901 +0000
@@ -19,7 +19,7 @@
 
 # No -DNDEBUG for Fortran.
 string(APPEND CMAKE_Fortran_FLAGS_MINSIZEREL_INIT " -Os")
-string(APPEND CMAKE_Fortran_FLAGS_RELEASE_INIT " -O3")
+string(APPEND CMAKE_Fortran_FLAGS_RELEASE_INIT " -O2")
 
 # No -isystem for Fortran because it will not find .mod files.
 unset(CMAKE_INCLUDE_SYSTEM_FLAG_Fortran)
diff -Naur cmake-3.18.2.orig/Modules/Compiler/GNU.cmake cmake-3.18.2/Modules/Compiler/GNU.cmake
--- cmake-3.18.2.orig/Modules/Compiler/GNU.cmake	2020-09-08 13:30:51.137086972 +0000
+++ cmake-3.18.2/Modules/Compiler/GNU.cmake	2020-09-10 08:44:38.939693578 +0000
@@ -56,7 +56,7 @@
   string(APPEND CMAKE_${lang}_FLAGS_INIT " ")
   string(APPEND CMAKE_${lang}_FLAGS_DEBUG_INIT " -g")
   string(APPEND CMAKE_${lang}_FLAGS_MINSIZEREL_INIT " -Os -DNDEBUG")
-  string(APPEND CMAKE_${lang}_FLAGS_RELEASE_INIT " -O3 -DNDEBUG")
+  string(APPEND CMAKE_${lang}_FLAGS_RELEASE_INIT " -O2 -DNDEBUG")
   string(APPEND CMAKE_${lang}_FLAGS_RELWITHDEBINFO_INIT " -O2 -g -DNDEBUG")
   set(CMAKE_${lang}_CREATE_PREPROCESSED_SOURCE "<CMAKE_${lang}_COMPILER> <DEFINES> <INCLUDES> <FLAGS> -E <SOURCE> > <PREPROCESSED_SOURCE>")
   set(CMAKE_${lang}_CREATE_ASSEMBLY_SOURCE "<CMAKE_${lang}_COMPILER> <DEFINES> <INCLUDES> <FLAGS> -S <SOURCE> -o <ASSEMBLY_SOURCE>")
diff -Naur cmake-3.18.2.orig/Modules/Compiler/Intel.cmake cmake-3.18.2/Modules/Compiler/Intel.cmake
--- cmake-3.18.2.orig/Modules/Compiler/Intel.cmake	2020-09-08 13:30:51.138086986 +0000
+++ cmake-3.18.2/Modules/Compiler/Intel.cmake	2020-09-10 08:44:25.749525964 +0000
@@ -22,7 +22,7 @@
     string(APPEND CMAKE_${lang}_FLAGS_INIT " ")
     string(APPEND CMAKE_${lang}_FLAGS_DEBUG_INIT " -g")
     string(APPEND CMAKE_${lang}_FLAGS_MINSIZEREL_INIT " -Os")
-    string(APPEND CMAKE_${lang}_FLAGS_RELEASE_INIT " -O3")
+    string(APPEND CMAKE_${lang}_FLAGS_RELEASE_INIT " -O2")
     string(APPEND CMAKE_${lang}_FLAGS_RELWITHDEBINFO_INIT " -O2 -g")
 
     set(CMAKE_${lang}_COMPILER_PREDEFINES_COMMAND "${CMAKE_${lang}_COMPILER}")
diff -Naur cmake-3.18.2.orig/Modules/Compiler/NVIDIA-CUDA.cmake cmake-3.18.2/Modules/Compiler/NVIDIA-CUDA.cmake
--- cmake-3.18.2.orig/Modules/Compiler/NVIDIA-CUDA.cmake	2020-09-08 13:30:51.138086986 +0000
+++ cmake-3.18.2/Modules/Compiler/NVIDIA-CUDA.cmake	2020-09-10 08:44:19.672448740 +0000
@@ -39,7 +39,7 @@
   set(CMAKE_SHARED_LIBRARY_CUDA_FLAGS -fPIC)
   string(APPEND CMAKE_CUDA_FLAGS_INIT " ")
   string(APPEND CMAKE_CUDA_FLAGS_DEBUG_INIT " -g")
-  string(APPEND CMAKE_CUDA_FLAGS_RELEASE_INIT " -O3 -DNDEBUG")
+  string(APPEND CMAKE_CUDA_FLAGS_RELEASE_INIT " -O2 -DNDEBUG")
   string(APPEND CMAKE_CUDA_FLAGS_MINSIZEREL_INIT " -O1 -DNDEBUG")
   string(APPEND CMAKE_CUDA_FLAGS_RELWITHDEBINFO_INIT " -O2 -g -DNDEBUG")
 endif()
diff -Naur cmake-3.18.2.orig/Modules/Compiler/PGI.cmake cmake-3.18.2/Modules/Compiler/PGI.cmake
--- cmake-3.18.2.orig/Modules/Compiler/PGI.cmake	2020-09-08 13:30:51.138086986 +0000
+++ cmake-3.18.2/Modules/Compiler/PGI.cmake	2020-09-10 08:44:32.995618043 +0000
@@ -18,7 +18,7 @@
   string(APPEND CMAKE_${lang}_FLAGS_INIT " ")
   string(APPEND CMAKE_${lang}_FLAGS_DEBUG_INIT " -g -O0")
   string(APPEND CMAKE_${lang}_FLAGS_MINSIZEREL_INIT " -O2 -s")
-  string(APPEND CMAKE_${lang}_FLAGS_RELEASE_INIT " -fast -O3")
+  string(APPEND CMAKE_${lang}_FLAGS_RELEASE_INIT " -fast -O2")
   string(APPEND CMAKE_${lang}_FLAGS_RELWITHDEBINFO_INIT " -O2 -gopt")
 
   if(CMAKE_HOST_WIN32)
diff -Naur cmake-3.18.2.orig/Modules/Compiler/PathScale.cmake cmake-3.18.2/Modules/Compiler/PathScale.cmake
--- cmake-3.18.2.orig/Modules/Compiler/PathScale.cmake	2020-09-08 13:30:51.138086986 +0000
+++ cmake-3.18.2/Modules/Compiler/PathScale.cmake	2020-09-10 08:44:16.715411163 +0000
@@ -16,6 +16,6 @@
   string(APPEND CMAKE_${lang}_FLAGS_INIT " ")
   string(APPEND CMAKE_${lang}_FLAGS_DEBUG_INIT " -g -O0")
   string(APPEND CMAKE_${lang}_FLAGS_MINSIZEREL_INIT " -Os")
-  string(APPEND CMAKE_${lang}_FLAGS_RELEASE_INIT " -O3")
+  string(APPEND CMAKE_${lang}_FLAGS_RELEASE_INIT " -O2")
   string(APPEND CMAKE_${lang}_FLAGS_RELWITHDEBINFO_INIT " -g -O2")
 endmacro()
diff -Naur cmake-3.18.2.orig/Modules/Platform/HP-UX-HP-CXX.cmake cmake-3.18.2/Modules/Platform/HP-UX-HP-CXX.cmake
--- cmake-3.18.2.orig/Modules/Platform/HP-UX-HP-CXX.cmake	2020-09-08 13:30:51.182087632 +0000
+++ cmake-3.18.2/Modules/Platform/HP-UX-HP-CXX.cmake	2020-09-10 08:44:00.226201627 +0000
@@ -9,6 +9,6 @@
   )
 
 string(APPEND CMAKE_CXX_FLAGS_DEBUG_INIT " -g")
-string(APPEND CMAKE_CXX_FLAGS_MINSIZEREL_INIT " +O3 -DNDEBUG")
+string(APPEND CMAKE_CXX_FLAGS_MINSIZEREL_INIT " +O2 -DNDEBUG")
 string(APPEND CMAKE_CXX_FLAGS_RELEASE_INIT " +O2 -DNDEBUG")
 string(APPEND CMAKE_CXX_FLAGS_RELWITHDEBINFO_INIT " -g")
diff -Naur cmake-3.18.2.orig/Modules/Platform/Windows-Clang.cmake cmake-3.18.2/Modules/Platform/Windows-Clang.cmake
--- cmake-3.18.2.orig/Modules/Platform/Windows-Clang.cmake	2020-09-08 13:30:51.185087676 +0000
+++ cmake-3.18.2/Modules/Platform/Windows-Clang.cmake	2020-09-10 08:44:07.269291127 +0000
@@ -79,7 +79,7 @@
 
     string(APPEND CMAKE_${lang}_FLAGS_DEBUG_INIT " -g -Xclang -gcodeview -O0 ${__ADDED_FLAGS_DEBUG}")
     string(APPEND CMAKE_${lang}_FLAGS_MINSIZEREL_INIT " -Os -DNDEBUG ${__ADDED_FLAGS}")
-    string(APPEND CMAKE_${lang}_FLAGS_RELEASE_INIT " -O3 -DNDEBUG ${__ADDED_FLAGS}")
+    string(APPEND CMAKE_${lang}_FLAGS_RELEASE_INIT " -O2 -DNDEBUG ${__ADDED_FLAGS}")
     string(APPEND CMAKE_${lang}_FLAGS_RELWITHDEBINFO_INIT " -O2 -g -DNDEBUG -Xclang -gcodeview ${__ADDED_FLAGS}")
   endif()
   set(CMAKE_INCLUDE_SYSTEM_FLAG_${lang} "-isystem ")