diff --git a/CMake/ConfigureCrossCompile.cmake b/CMake/ConfigureCrossCompile.cmake
index a320d32932..0a39b829ed 100644
--- a/CMake/ConfigureCrossCompile.cmake
+++ b/CMake/ConfigureCrossCompile.cmake
@@ -28,6 +28,7 @@ macro(search_openblas version)
     get_deps(https://github.com/xianyi/OpenBLAS/releases/download/v${version}/OpenBLAS-${version}.tar.gz OpenBLAS OpenBLAS-${version}.tar.gz)
     if (NOT MSVC)
       if (NOT EXISTS "${CMAKE_BINARY_DIR}/deps/OpenBLAS-${version}/libopenblas.a")
+        set(ENV{COMMON_OPT} "${CMAKE_OPENBLAS_FLAGS}") # Pass our flags to OpenBLAS
         execute_process(COMMAND make TARGET=${OPENBLAS_TARGET} BINARY=${OPENBLAS_BINARY} HOSTCC=gcc CC=${CMAKE_C_COMPILER} FC=${CMAKE_FORTRAN_COMPILER} NO_SHARED=1
                         WORKING_DIRECTORY ${CMAKE_BINARY_DIR}/deps/OpenBLAS-${version})
       endif()
diff --git a/CMakeLists.txt b/CMakeLists.txt
index f530697ca9..ced015958b 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -249,8 +249,12 @@ if (DEBUG)
 else()
   add_definitions(-DNDEBUG)
   if (NOT MSVC)
-    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -O3")
-    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -std=c99 -O3")
+    if (NOT CMAKE_CROSSCOMPILING)
+      set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -O3")
+      set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -std=c99 -O3")
+    else()
+      set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -std=c99")
+    endif()
   else ()
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /O3")
     set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} /O3")
@@ -283,7 +287,7 @@ endif()
 # Download and compile OpenBLAS if we are cross compiling mlpack for a specific
 # architecture. The function takes the version of OpenBLAS as variable.
 if (CMAKE_CROSSCOMPILING)
-  search_openblas(0.3.13)
+  search_openblas(0.3.26)
 endif()
 
 if (NOT DOWNLOAD_DEPENDENCIES)
diff --git a/board/flags-config.cmake b/board/flags-config.cmake
index 94b2060b44..5999ab86ac 100644
--- a/board/flags-config.cmake
+++ b/board/flags-config.cmake
@@ -4,63 +4,86 @@
 # footprints.
 
 # Set generic minimization flags for all platforms.
-# These flags are the same for all cross-compilation cases.
-set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Os -fdata-sections -ffunction-sections")
+# These flags are the same for all cross-compilation cases and they are
+# mainly to reduce the binary footprint.
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Os -s -fdata-sections -ffunction-sections")
 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fomit-frame-pointer -fno-unwind-tables")
 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fno-asynchronous-unwind-tables -fvisibility=hidden")
 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fshort-enums -finline-small-functions")
 set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -findirect-inlining -fno-common")
-#-flto -fuse-ld=gold # There is an issue with gold link when compiling on 
-# Ubuntu 16. At that point gcc linker did not integrate the flto support 
-# inside and it was a separate plugin that need to be added. Therefore, 
-# this can be added when mlpack Azure CI moves toward Ubuntu 20.
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fmerge-all-constants -fno-ident")
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fno-unroll-loops -fno-math-errno")
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fno-stack-protector")
+set(CMAKE_OPENBLAS_FLAGS "${CMAKE_CXX_FLAGS}") # OpenBLAS does not supoport flto
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -flto")
+set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,--hash-style=gnu -Wl,--build-id=none")
+set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,-z,norelro")
+set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,--gc-sections")
+## Keep the following flag in comment, they might be relevant in the case of MCU's
+#set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wl,-nmagic,-Bsymbolic -nostartfiles")
 
 set(BOARD_NAME "" CACHE STRING "Specify Board name to optimize for.")
 string(TOUPPER ${BOARD_NAME} BOARD)
 
 # Set specific platforms CMAKE CXX flags.
-if(BOARD MATCHES "RPI0" OR BOARD MATCHES "RPI1")
+if(BOARD MATCHES "RPI0" OR BOARD MATCHES "RPI1" OR BOARD MATCHES "ARM11")
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -mtune=arm1176jzf-s")
-  set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,--gc-sections")
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -mcpu=arm1176jzf-s -mfloat-abi=hard -mfpu=vfp")
   set(OPENBLAS_TARGET "ARMV6")
   set(OPENBLAS_BINARY "32")
-elseif(BOARD MATCHES "RPI2")
+elseif(BOARD MATCHES "RPI2" OR BOARD MATCHES "CORTEXA7")
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -mtune=cortex-a7")
-  set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,--gc-sections")
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -mfloat-abi=hard -mfpu=neon-vfpv4")
   set(OPENBLAS_TARGET "ARMV7")
   set(OPENBLAS_BINARY "32")
-elseif(BOARD MATCHES "RPI3")
-  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -mtune=cortex-a53")
-  set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,--gc-sections")
+elseif(BOARD MATCHES "CORTEXA8")
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -mtune=cortex-a8")
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -mfloat-abi=hard -mfpu=neon")
+  set(OPENBLAS_TARGET "ARMV7")
+  set(OPENBLAS_BINARY "32")
+elseif(BOARD MATCHES "CORTEXA9")
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -mtune=cortex-a9")
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -mfloat-abi=hard -mfpu=neon")
+  set(OPENBLAS_TARGET "CORTEXA9")
+  set(OPENBLAS_BINARY "32")
+elseif(BOARD MATCHES "CORTEXA15")
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -mtune=cortex-a15")
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -mfloat-abi=hard -mfpu=neon")
+  set(OPENBLAS_TARGET "CORTEXA15")
+  set(OPENBLAS_BINARY "32")
+elseif(BOARD MATCHES "RPI3" OR BOARD MATCHES "CORTEXA53")
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -mtune=cortex-a53 -ftree-vectorize")
   set(OPENBLAS_TARGET "CORTEXA53")
   set(OPENBLAS_BINARY "64")
-elseif(BOARD MATCHES "RPI4")
-  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -mtune=cortex-a72")
-  set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,--gc-sections")
+elseif(BOARD MATCHES "RPI4" OR BOARD MATCHES "CORTEXA72")
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -mtune=cortex-a72 -ftree-vectorize")
   set(OPENBLAS_TARGET "CORTEXA72")
   set(OPENBLAS_BINARY "64")
+elseif(BOARD MATCHES "JETSONAGX" OR BOARD MATCHES "CORTEXA76")
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -mtune=cortex-a76 -ftree-vectorize")
+  set(OPENBLAS_TARGET "CORTEXA76")
+  set(OPENBLAS_BINARY "64")
 elseif(BOARD MATCHES "BV")
-  set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,--gc-sections")
   set(OPENBLAS_TARGET "RISCV64_GENERIC")
   set(OPENBLAS_BINARY "64")
-elseif(BOARD MATCHES "JETSONAGX")
-  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -matune=cortex-a76")
-  set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,--gc-sections")
-  set(OPENBLAS_TARGET "ARM8")
+elseif(BOARD MATCHES "C906")
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -mtune=thead-c906")
+  set(OPENBLAS_TARGET "RISCV64_GENERIC")
+  set(OPENBLAS_BINARY "64")
+elseif(BOARD MATCHES "x280")
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -mtune=sifive-x280")
+  set(OPENBLAS_TARGET "x280")
   set(OPENBLAS_BINARY "64")
 elseif(BOARD MATCHES "KATAMI")
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -march=pentium3")
-  set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,--gc-sections")
   set(OPENBLAS_TARGET "KATAMI")
   set(OPENBLAS_BINARY "32")
 elseif(BOARD MATCHES "COPPERMINE")
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -march=pentium3")
-  set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,--gc-sections")
   set(OPENBLAS_TARGET "COPPERMINE")
   set(OPENBLAS_BINARY "32")
 elseif(BOARD MATCHES "NORTHWOOD")
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -march=pentium4")
-  set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,--gc-sections")
   set(OPENBLAS_TARGET "NORTHWOOD")
   set(OPENBLAS_BINARY "32")
 elseif(BOARD)