__attribute__((__packed__)) not accepted.

CCS v4.4.1 with --gcc enabled, compiler doc has this example:

  struct __attribute__((__packed__)) packed_struct { char c1; int i; char c2; };

Compilation fails with: "App.c", line 140: error #1167: invalid attribute for "struct packed_struct" 1 error detected in the compilation of "App.c".

I have tried various other uses of __attribute__((__packed__)); It seems the compiler does not accept it at all?

 BR. Leo.