ARMC5 build is failing mbed-os-5-15-rc2 for k64f in linux

[saheerb]

Description of defect

Build is failing in this combination:
mbed-os-5-15-rc2,
application: mbed-os-example-blink
host: linux
toolchain: ARMC5 Version:
Target: K64F

Full log file:

https://btools-build-results.s3-us-west-2.amazonaws.com/production/production-nightly/88/logs/compilation_target_k64f_toolchain_armc5_os_version_latest_host_platform_linux_example_baseline_blinky_all_hosts.txt

This is a regression from mbed-os-5-15-rc1

Target(s) affected by this defect ?

K64F

Toolchain(s) (name and version) displaying this defect ?

ARMC5,

What version of Mbed-os are you using (tag or sha) ?

mbed-os-5-15-rc2

What version(s) of tools are you using. List all that apply (E.g. mbed-cli)

How is this defect reproduced ?

mbed compile

[ciarmcom]

Internal Jira reference: https://jira.arm.com/browse/MBOTRIAGE-2471

[jamesbeyond]

This is because of the static pinmap feature we introduced, it used constexpr keyword in https://github.com/ARMmbed/mbed-os/blob/master/features/storage/kvstore/conf/kv_config.cpp#L54

the constexpr is part of C++14 standard which ARMC5 is not supporting, hence resulting in the issue, on all other compliers, GCC_ARM 6 or later, ARMC6.13 IAR8.x they are fine with constexpr

[0xc0170]

Just making sure, @jamesbeyond 5.15 release notes contain this info about it : STATIC_PINMAP_READY targets wont compile with ARMC5 or similar?

cc @adbridge

[kjbracey]

Fixed by #12117 - closing.