building arm-trusted-firmware fails with /usr/bin/aarch64-linux-musl-gcc: 1: Syntax error: "(" unexpected

[as365n4]

I am trying to build the firmware for a Pine64 H64B board and I have set the board selection in the meta Makefile to pine_h64, but make fails with the below error output.

  CHECK   board
  CLONE   arm-trusted-firmware
Cloning into 'arm-trusted-firmware'...
remote: Enumerating objects: 101371, done.
remote: Counting objects: 100% (2/2), done.
remote: Compressing objects: 100% (2/2), done.
remote: Total 101371 (delta 0), reused 0 (delta 0), pack-reused 101369
Receiving objects: 100% (101371/101371), 25.38 MiB | 2.42 MiB/s, done.
Resolving deltas: 100% (65353/65353), done.
Updating files: 100% (3855/3855), done.
  MAKE    arm-trusted-firmware/build/sun50i_h6/release/bl31.bin
make[1]: Entering directory '/home/user/meta/arm-trusted-firmware'
  CC      bl31/bl31_context_mgmt.c
/usr/bin/aarch64-linux-musl-gcc: 1: Syntax error: "(" unexpected
make[1]: *** [Makefile:1308: /home/user/meta/arm-trusted-firmware/build/sun50i_h6/release/bl31/bl31_context_mgmt.o] Error 2
make[1]: Leaving directory '/home/user/meta/arm-trusted-firmware'
make: *** [Makefile:90: arm-trusted-firmware/build/sun50i_h6/release/bl31.bin] Error 2