toggle.c: compilation error

#msp430-gcc version is 4.5.3
#msp430-gcc -mmcu=msp430f235 toggle.c
toggle.c:5:1: warning: data definition has no type or storage class
toggle.c:5:1: error: conflicting type qualifiers for ‘BSLSKEY’
toggle.c:4:1: note: previous declaration of ‘BSLSKEY’ was here