------- Comment #4 from eweddington at cso dot atmel dot com 2007-04-04 00:38 ------- Confirmed bug.
shifty3.i is a test case showing the problem. Compiled with avr-gcc 4.1.2, with: avr-gcc -Os shifty.c -o shifty.o shifty3.dis is a disassembly of shifty.o (with avr-objdump -d shifty.o). The problem is exhibited here: 0000005a <main>: 5a: 89 e2 ldi r24, 0x29 ; 41 5c: 90 e0 ldi r25, 0x00 ; 0 5e: 90 93 61 00 sts 0x0061, r25 62: 80 93 60 00 sts 0x0060, r24 66: 82 e5 ldi r24, 0x52 ; 82 68: 92 e0 ldi r25, 0x02 ; 2 6a: 90 93 64 00 sts 0x0064, r25 6e: 80 93 63 00 sts 0x0063, r24 72: e0 91 60 00 lds r30, 0x0060 76: f0 91 61 00 lds r31, 0x0061 7a: 09 95 icall 7c: e0 91 63 00 lds r30, 0x0063 80: f0 91 64 00 lds r31, 0x0064 84: 09 95 icall The correct word address of the function foo is taken and stored (address 5a to 62), but then the *byte* address of the function foo is taken, and an offset added, and stored (address 66 to 6e). The following indirect call (address 7c to 84) is then incorrect. The PC has to be a *word* address. Adding a fixed offset to a function pointer, and then doing an indirect call, is valid in an AVR application as it is possible to copy or place functions at fixed offsets like this. Please mark this bug as NEW. Known to fail: 4.1.1, 4.1.2 -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=27192
