They don't seem to have been generated right:
.TH "interrupt.h" 3 "15 May 2007" "Version 1.4.6" "avr-libc" \" -*- nroff -*- .ad l .nh .SH NAME interrupt.h \- .SH "Detailed Description" .PP @{ .SH SYNOPSIS .br .PP .SS "Global manipulation of the interrupt flag" The global interrupt flag is maintained in the I bit of the status register (SREG). .in +1c .ti -1c .RI "#define \fBsei\fP()" .br .ti -1c .RI "#define \fBcli\fP()" .br .in -1c .SS "Macros for writing interrupt handler functions" .in +1c .ti -1c .RI "#define \fBISR\fP(vector)" .br .ti -1c .RI "#define \fBSIGNAL\fP(vector)" .br .ti -1c .RI "#define \fBEMPTY_INTERRUPT\fP(vector)" .br .ti -1c .RI "#define \fBISR_ALIAS\fP(vector, target_vector)" .br .in -1c .SH "Author" .PP Generated automatically by Doxygen for avr-libc from the source code.
:( Is this an avr-libc problem, or winavr compilation problem?