Hi Archanaa,

By disabling MBEDTLS_PLATFORM_MEMORY and MBEDTLS_PLATFORM_C, you should also need to disable some other macros like MBEDTLS_MEMORY_BUFFER_ALLOC_C since mbedtls will do some dependency check.
I just used tfm default profile medium config to have a try, it can build successfully. 
Is it possible to show me your customized mbedcrypto configuration and build command? It will be helpful to know the issue you have ~

Best Wishes
Summer 
From: S Krishnan, Archanaa via TF-M <tf-m@lists.trustedfirmware.org>
Sent: Thursday, September 28, 2023 6:04 AM
To: tf-m@lists.trustedfirmware.org <tf-m@lists.trustedfirmware.org>
Subject: [TF-M] Build error with customized mbedcrypto configuration
 

Hello,

 

I am trying to build TF-M v1.8 with a custom tfm_mbedcrypto_config_profile_medium.h . I mainly do not want to use a platform specific calloc /free calls, instead use standard free() and calloc(). If I disable MBEDTLS_PLATFORM_MEMORY and MBEDTLS_PLATFORM_C in tfm_mbedcrypto_config_profile_medium.h and attempt to build TF-M, I get the following error:


/arm-none-eabi/lib/thumb/v8-m.main+fp/hard/libnosys.a(sbrk.o): in function `_sbrk':

/data/jenkins/workspace/GNU-toolchain/arm-11/src/newlib-cygwin/libgloss/libnosys/sbrk.c:21: undefined reference to `end'

 

I’m able to build mbedtls package with both MBEDTLS_PLATFORM_MEMORY and MBEDTLS_PLATFORM_C disabled without any errors, the undefined reference error is only seen when building TF-M.

 

Any thoughts on how to resolve this?

 

Regards,
Archanaa