diff --git a/targets/CMSIS-OS/ChibiOS/MBN_QUAIL/CMakeLists.txt b/targets/CMSIS-OS/ChibiOS/MBN_QUAIL/CMakeLists.txt
index fce43366ef..a1841f619b 100644
--- a/targets/CMSIS-OS/ChibiOS/MBN_QUAIL/CMakeLists.txt
+++ b/targets/CMSIS-OS/ChibiOS/MBN_QUAIL/CMakeLists.txt
@@ -174,8 +174,8 @@ nf_set_linker_options(${NANOCLR_PROJECT_NAME}.elf TRUE)
 ###################################################
 # the size of the CLR managed heap is defined here
 ###################################################
-set_property(TARGET ${NANOBOOTER_PROJECT_NAME}.elf APPEND_STRING PROPERTY LINK_FLAGS ",--defsym=__main_stack_size__=0x400,--defsym=__process_stack_size__=0x400,--defsym=__clr_managed_heap_size__=0x0")
-set_property(TARGET ${NANOCLR_PROJECT_NAME}.elf APPEND_STRING PROPERTY LINK_FLAGS ",--defsym=__main_stack_size__=0x400,--defsym=__process_stack_size__=0x400,--defsym=__clr_managed_heap_size__=0x9000")
+set_property(TARGET ${NANOBOOTER_PROJECT_NAME}.elf APPEND_STRING PROPERTY LINK_FLAGS ",--defsym=__main_stack_size__=0x400,--defsym=__process_stack_size__=0x400,--defsym=__crt_heap_size__=0x400")
+set_property(TARGET ${NANOCLR_PROJECT_NAME}.elf APPEND_STRING PROPERTY LINK_FLAGS ",--defsym=__main_stack_size__=0x400,--defsym=__process_stack_size__=0x800,--defsym=__crt_heap_size__=0x1800")
 
 # generate output files
 nf_generate_build_output_files(${NANOBOOTER_PROJECT_NAME}.elf)
diff --git a/targets/CMSIS-OS/ChibiOS/NETDUINO3_WIFI/CMakeLists.txt b/targets/CMSIS-OS/ChibiOS/NETDUINO3_WIFI/CMakeLists.txt
index 8f2a87262a..84886728e8 100644
--- a/targets/CMSIS-OS/ChibiOS/NETDUINO3_WIFI/CMakeLists.txt
+++ b/targets/CMSIS-OS/ChibiOS/NETDUINO3_WIFI/CMakeLists.txt
@@ -174,8 +174,8 @@ nf_set_linker_options(${NANOCLR_PROJECT_NAME}.elf TRUE)
 ###################################################
 # the size of the CLR managed heap is defined here
 ###################################################
-set_property(TARGET ${NANOBOOTER_PROJECT_NAME}.elf APPEND_STRING PROPERTY LINK_FLAGS ",--defsym=__main_stack_size__=0x400,--defsym=__process_stack_size__=0x400,--defsym=__clr_managed_heap_size__=0x0")
-set_property(TARGET ${NANOCLR_PROJECT_NAME}.elf APPEND_STRING PROPERTY LINK_FLAGS ",--defsym=__main_stack_size__=0x400,--defsym=__process_stack_size__=0x400,--defsym=__clr_managed_heap_size__=0x9000")
+set_property(TARGET ${NANOBOOTER_PROJECT_NAME}.elf APPEND_STRING PROPERTY LINK_FLAGS ",--defsym=__main_stack_size__=0x400,--defsym=__process_stack_size__=0x400,--defsym=__crt_heap_size__=0x400")
+set_property(TARGET ${NANOCLR_PROJECT_NAME}.elf APPEND_STRING PROPERTY LINK_FLAGS ",--defsym=__main_stack_size__=0x400,--defsym=__process_stack_size__=0x800,--defsym=__crt_heap_size__=0x1800")
 
 # generate output files
 nf_generate_build_output_files(${NANOBOOTER_PROJECT_NAME}.elf)
diff --git a/targets/CMSIS-OS/ChibiOS/ST_NUCLEO144_F746ZG/CMakeLists.txt b/targets/CMSIS-OS/ChibiOS/ST_NUCLEO144_F746ZG/CMakeLists.txt
index 606443af58..98e479155a 100644
--- a/targets/CMSIS-OS/ChibiOS/ST_NUCLEO144_F746ZG/CMakeLists.txt
+++ b/targets/CMSIS-OS/ChibiOS/ST_NUCLEO144_F746ZG/CMakeLists.txt
@@ -174,8 +174,8 @@ nf_set_linker_options(${NANOCLR_PROJECT_NAME}.elf TRUE)
 ###################################################
 # the size of the CLR managed heap is defined here
 ###################################################
-set_property(TARGET ${NANOBOOTER_PROJECT_NAME}.elf APPEND_STRING PROPERTY LINK_FLAGS ",--defsym=__main_stack_size__=0x400,--defsym=__process_stack_size__=0x400,--defsym=__clr_managed_heap_size__=0x0")
-set_property(TARGET ${NANOCLR_PROJECT_NAME}.elf APPEND_STRING PROPERTY LINK_FLAGS ",--defsym=__main_stack_size__=0x400,--defsym=__process_stack_size__=0x400,--defsym=__clr_managed_heap_size__=0x2B000")
+set_property(TARGET ${NANOBOOTER_PROJECT_NAME}.elf APPEND_STRING PROPERTY LINK_FLAGS ",--defsym=__main_stack_size__=0x400,--defsym=__process_stack_size__=0x400,--defsym=__crt_heap_size__=0x400")
+set_property(TARGET ${NANOCLR_PROJECT_NAME}.elf APPEND_STRING PROPERTY LINK_FLAGS ",--defsym=__main_stack_size__=0x400,--defsym=__process_stack_size__=0x800,--defsym=__crt_heap_size__=0x1800")
 
 # generate output files
 nf_generate_build_output_files(${NANOBOOTER_PROJECT_NAME}.elf)
diff --git a/targets/CMSIS-OS/ChibiOS/ST_NUCLEO144_F746ZG/nanoCLR/STM32F746xG_CLR.ld b/targets/CMSIS-OS/ChibiOS/ST_NUCLEO144_F746ZG/nanoCLR/STM32F746xG_CLR.ld
index 8f3cb067db..66fbae064f 100644
--- a/targets/CMSIS-OS/ChibiOS/ST_NUCLEO144_F746ZG/nanoCLR/STM32F746xG_CLR.ld
+++ b/targets/CMSIS-OS/ChibiOS/ST_NUCLEO144_F746ZG/nanoCLR/STM32F746xG_CLR.ld
@@ -119,17 +119,8 @@ SECTIONS
 /* Code rules inclusion.*/
 INCLUDE rules_code.ld
 
-/*  
-/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// 
-// rules_clr.ld have to be included **BEFORE** the rules_data.ld 
-// this is because the CRT heap (processed in rules_data.ld) takes up all the remaining free space of the memory region where it's assigned 
-// the size of the managed heap (processed in rules_clr.ld) is set in each target configuration 
-// in case it shares the same region as the CRT heap it won't have any room left if the CRT heap is assigned first 
-/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// 
-/*  
+/* Data rules inclusion.*/
+INCLUDE rules_data.ld
 
 /* nanoCLR rules inclusion.*/
 INCLUDE rules_clr.ld
-
-/* Data rules inclusion.*/
-INCLUDE rules_data.ld
\ No newline at end of file
diff --git a/targets/CMSIS-OS/ChibiOS/ST_NUCLEO64_F091RC/CMakeLists.txt b/targets/CMSIS-OS/ChibiOS/ST_NUCLEO64_F091RC/CMakeLists.txt
index e4c55d2ac7..1ba39eb7c9 100644
--- a/targets/CMSIS-OS/ChibiOS/ST_NUCLEO64_F091RC/CMakeLists.txt
+++ b/targets/CMSIS-OS/ChibiOS/ST_NUCLEO64_F091RC/CMakeLists.txt
@@ -174,8 +174,8 @@ nf_set_linker_options(${NANOCLR_PROJECT_NAME}.elf TRUE)
 ###################################################
 # the size of the CLR managed heap is defined here
 ###################################################
-set_property(TARGET ${NANOBOOTER_PROJECT_NAME}.elf APPEND_STRING PROPERTY LINK_FLAGS ",--defsym=__main_stack_size__=0x400,--defsym=__process_stack_size__=0x400,--defsym=__clr_managed_heap_size__=0x0")
-set_property(TARGET ${NANOCLR_PROJECT_NAME}.elf APPEND_STRING PROPERTY LINK_FLAGS ",--defsym=__main_stack_size__=0x400,--defsym=__process_stack_size__=0x400,--defsym=__clr_managed_heap_size__=0x2000")
+set_property(TARGET ${NANOBOOTER_PROJECT_NAME}.elf APPEND_STRING PROPERTY LINK_FLAGS ",--defsym=__main_stack_size__=0x400,--defsym=__process_stack_size__=0x400,--defsym=__crt_heap_size__=0x400")
+set_property(TARGET ${NANOCLR_PROJECT_NAME}.elf APPEND_STRING PROPERTY LINK_FLAGS ",--defsym=__main_stack_size__=0x400,--defsym=__process_stack_size__=0x800,--defsym=__crt_heap_size__=0x1800")
 
 # generate output files
 nf_generate_build_output_files(${NANOBOOTER_PROJECT_NAME}.elf)
diff --git a/targets/CMSIS-OS/ChibiOS/ST_STM32F429I_DISCOVERY/CMakeLists.txt b/targets/CMSIS-OS/ChibiOS/ST_STM32F429I_DISCOVERY/CMakeLists.txt
index 2e60c295e5..79f04e28c7 100644
--- a/targets/CMSIS-OS/ChibiOS/ST_STM32F429I_DISCOVERY/CMakeLists.txt
+++ b/targets/CMSIS-OS/ChibiOS/ST_STM32F429I_DISCOVERY/CMakeLists.txt
@@ -174,8 +174,8 @@ nf_set_linker_options(${NANOCLR_PROJECT_NAME}.elf TRUE)
 ###################################################
 # the size of the CLR managed heap is defined here
 ###################################################
-set_property(TARGET ${NANOBOOTER_PROJECT_NAME}.elf APPEND_STRING PROPERTY LINK_FLAGS ",--defsym=__main_stack_size__=0x400,--defsym=__process_stack_size__=0x400,--defsym=__clr_managed_heap_size__=0x0")
-set_property(TARGET ${NANOCLR_PROJECT_NAME}.elf APPEND_STRING PROPERTY LINK_FLAGS ",--defsym=__main_stack_size__=0x400,--defsym=__process_stack_size__=0x400,--defsym=__clr_managed_heap_size__=0x29600")
+set_property(TARGET ${NANOBOOTER_PROJECT_NAME}.elf APPEND_STRING PROPERTY LINK_FLAGS ",--defsym=__main_stack_size__=0x400,--defsym=__process_stack_size__=0x400,--defsym=__crt_heap_size__=0x400")
+set_property(TARGET ${NANOCLR_PROJECT_NAME}.elf APPEND_STRING PROPERTY LINK_FLAGS ",--defsym=__main_stack_size__=0x400,--defsym=__process_stack_size__=0x800,--defsym=__crt_heap_size__=0x1800")
 
 # generate output files
 nf_generate_build_output_files(${NANOBOOTER_PROJECT_NAME}.elf)
diff --git a/targets/CMSIS-OS/ChibiOS/ST_STM32F4_DISCOVERY/CMakeLists.txt b/targets/CMSIS-OS/ChibiOS/ST_STM32F4_DISCOVERY/CMakeLists.txt
index 680c53ba79..13b95425bd 100644
--- a/targets/CMSIS-OS/ChibiOS/ST_STM32F4_DISCOVERY/CMakeLists.txt
+++ b/targets/CMSIS-OS/ChibiOS/ST_STM32F4_DISCOVERY/CMakeLists.txt
@@ -174,8 +174,8 @@ nf_set_linker_options(${NANOCLR_PROJECT_NAME}.elf TRUE)
 ###################################################
 # the size of the CLR managed heap is defined here
 ###################################################
-set_property(TARGET ${NANOBOOTER_PROJECT_NAME}.elf APPEND_STRING PROPERTY LINK_FLAGS ",--defsym=__main_stack_size__=0x400,--defsym=__process_stack_size__=0x400,--defsym=__clr_managed_heap_size__=0x0")
-set_property(TARGET ${NANOCLR_PROJECT_NAME}.elf APPEND_STRING PROPERTY LINK_FLAGS ",--defsym=__main_stack_size__=0x400,--defsym=__process_stack_size__=0x400,--defsym=__clr_managed_heap_size__=0x196C0")
+set_property(TARGET ${NANOBOOTER_PROJECT_NAME}.elf APPEND_STRING PROPERTY LINK_FLAGS ",--defsym=__main_stack_size__=0x400,--defsym=__process_stack_size__=0x400,--defsym=__crt_heap_size__=0x400")
+set_property(TARGET ${NANOCLR_PROJECT_NAME}.elf APPEND_STRING PROPERTY LINK_FLAGS ",--defsym=__main_stack_size__=0x400,--defsym=__process_stack_size__=0x800,--defsym=__crt_heap_size__=0x1800")
 
 # generate output files
 nf_generate_build_output_files(${NANOBOOTER_PROJECT_NAME}.elf)
diff --git a/targets/CMSIS-OS/ChibiOS/ST_STM32F769I_DISCOVERY/CMakeLists.txt b/targets/CMSIS-OS/ChibiOS/ST_STM32F769I_DISCOVERY/CMakeLists.txt
index 657045bf5e..3022439bc0 100644
--- a/targets/CMSIS-OS/ChibiOS/ST_STM32F769I_DISCOVERY/CMakeLists.txt
+++ b/targets/CMSIS-OS/ChibiOS/ST_STM32F769I_DISCOVERY/CMakeLists.txt
@@ -174,8 +174,8 @@ nf_set_linker_options(${NANOCLR_PROJECT_NAME}.elf TRUE)
 ###################################################
 # the size of the CLR managed heap is defined here
 ###################################################
-set_property(TARGET ${NANOBOOTER_PROJECT_NAME}.elf APPEND_STRING PROPERTY LINK_FLAGS ",--defsym=__main_stack_size__=0x400,--defsym=__process_stack_size__=0x400,--defsym=__clr_managed_heap_size__=0x0")
-set_property(TARGET ${NANOCLR_PROJECT_NAME}.elf APPEND_STRING PROPERTY LINK_FLAGS ",--defsym=__main_stack_size__=0x400,--defsym=__process_stack_size__=0x400,--defsym=__clr_managed_heap_size__=0x4B000")
+set_property(TARGET ${NANOBOOTER_PROJECT_NAME}.elf APPEND_STRING PROPERTY LINK_FLAGS ",--defsym=__main_stack_size__=0x400,--defsym=__process_stack_size__=0x400,--defsym=__crt_heap_size__=0x400")
+set_property(TARGET ${NANOCLR_PROJECT_NAME}.elf APPEND_STRING PROPERTY LINK_FLAGS ",--defsym=__main_stack_size__=0x400,--defsym=__process_stack_size__=0x800,--defsym=__crt_heap_size__=0x1800")
 
 # generate output files
 nf_generate_build_output_files(${NANOBOOTER_PROJECT_NAME}.elf)
diff --git a/targets/CMSIS-OS/ChibiOS/ST_STM32F769I_DISCOVERY/nanoCLR/STM32F76xx_CLR.ld b/targets/CMSIS-OS/ChibiOS/ST_STM32F769I_DISCOVERY/nanoCLR/STM32F76xx_CLR.ld
index 6eb478991e..c8d18b07d6 100644
--- a/targets/CMSIS-OS/ChibiOS/ST_STM32F769I_DISCOVERY/nanoCLR/STM32F76xx_CLR.ld
+++ b/targets/CMSIS-OS/ChibiOS/ST_STM32F769I_DISCOVERY/nanoCLR/STM32F76xx_CLR.ld
@@ -119,17 +119,8 @@ SECTIONS
 /* Code rules inclusion.*/
 INCLUDE rules_code.ld
 
-/*  
-/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// 
-// rules_clr.ld have to be included **BEFORE** the rules_data.ld 
-// this is because the CRT heap (processed in rules_data.ld) takes up all the remaining free space of the memory region where it's assigned 
-// the size of the managed heap (processed in rules_clr.ld) is set in each target configuration 
-// in case it shares the same region as the CRT heap it won't have any room left if the CRT heap is assigned first 
-/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////// 
-/*  
+/* Data rules inclusion.*/
+INCLUDE rules_data.ld
 
 /* nanoCLR rules inclusion.*/
 INCLUDE rules_clr.ld
-
-/* Data rules inclusion.*/
-INCLUDE rules_data.ld
\ No newline at end of file
diff --git a/targets/CMSIS-OS/ChibiOS/common/rules.ld b/targets/CMSIS-OS/ChibiOS/common/rules.ld
index e2e42b2e8f..4e323fa89c 100644
--- a/targets/CMSIS-OS/ChibiOS/common/rules.ld
+++ b/targets/CMSIS-OS/ChibiOS/common/rules.ld
@@ -12,18 +12,8 @@ INCLUDE rules_stacks.ld
 /* Code rules inclusion.*/
 INCLUDE rules_code.ld
 
-
-/* 
-///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
-// rules_clr.ld have to be included **BEFORE** the rules_data.ld
-// this is because the CRT heap (processed in rules_data.ld) takes up all the remaining free space of the memory region where it's assigned
-// the size of the managed heap (processed in rules_clr.ld) is set in each target configuration
-// in case it shares the same region as the CRT heap it won't have any room left if the CRT heap is assigned first
-///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
-/* 
+/* Data rules inclusion.*/
+INCLUDE rules_data.ld
 
 /* nanoCLR rules inclusion.*/
 INCLUDE rules_clr.ld
-
-/* Data rules inclusion.*/
-INCLUDE rules_data.ld
diff --git a/targets/CMSIS-OS/ChibiOS/common/rules_clr.ld b/targets/CMSIS-OS/ChibiOS/common/rules_clr.ld
index 00916afb8c..80cedd4f5c 100644
--- a/targets/CMSIS-OS/ChibiOS/common/rules_clr.ld
+++ b/targets/CMSIS-OS/ChibiOS/common/rules_clr.ld
@@ -1,21 +1,21 @@
  SECTIONS
 {
  
- /* nanoFramework CLR managed heap section at the specified RAM section.*/
+    /* nanoFramework CLR managed heap section at the specified RAM section.*/
     .clr_managed_heap (NOLOAD) :
     {
         . = ALIGN(8);
-        PROVIDE(HeapBegin = LOADADDR(.clr_managed_heap));
         __clr_managed_heap_base__ = .;
-        . += __clr_managed_heap_size__;
+        PROVIDE(HeapBegin = LOADADDR(.clr_managed_heap));
+        . = ORIGIN(CLR_MANAGED_HEAP_RAM) + LENGTH(CLR_MANAGED_HEAP_RAM) - LENGTH(ramvt);
         . = ALIGN(8);
         __clr_managed_heap_end__ = .;
         PROVIDE(HeapEnd = .);
     } > CLR_MANAGED_HEAP_RAM
 
-        /* RAM space reserved for the vector table */
+    /* RAM space reserved for the vector table */
     .RAMVectorTable (NOLOAD) : ALIGN(4)
     {
         *(.RAMVectorTable)
     } > ramvt
-}
\ No newline at end of file
+}
diff --git a/targets/CMSIS-OS/ChibiOS/common/rules_data.ld b/targets/CMSIS-OS/ChibiOS/common/rules_data.ld
index 1986413d02..78bcf5e789 100644
--- a/targets/CMSIS-OS/ChibiOS/common/rules_data.ld
+++ b/targets/CMSIS-OS/ChibiOS/common/rules_data.ld
@@ -266,7 +266,8 @@ SECTIONS
     {
         . = ALIGN(8);
         __heap_base__ = .;
-        . = ORIGIN(HEAP_RAM) + LENGTH(HEAP_RAM);
+        . += __crt_heap_size__;
+        . = ALIGN(8);
         __heap_end__ = .;
     } > HEAP_RAM
 }