Does a target system must support indexing? I have tried to disable indexing by setting the following macros: #define INDEX_REG_CLASS NO_REGS #define REGNO_OK_FOR_INDEX_P(num) 0 and rejecting all addresses with side effects in the target hook TARGET_LEGITIMATE_ADDRESS_P. But it seems that the compiler still trying to use indexes. For example the compiler fails at: C-code: void fail(long long *v) { *v += 1; } Failure: fail.c: In function 'fail': fail.c:4:1: internal compiler error: in change_address_1, at emit-rtl.c:1933 Please submit a full bug report, with preprocessed source if appropriate. See <http://gcc.gnu.org/bugs.html> for instructions. Last debug info from TARGET_LEGITIMATE_ADDRESS_P: legitimate_address_p: mode: (SI) (reload_completed) (reg_renumber): (r18 ---> r18) address: (plus:SI (reg/f:SI 18 r18) (const_int 4 [0x4])) return false I am not sure if it fails because of the index or i made some mistakes in describing the handling of long long values. But still. Why the compiler tried to use indexing? PS: - the debug output in TARGET_LEGITIMATE_ADDRESS_P is stollen from the avr backend - r18 is the frame pointer - sorry for my bad englisch. i am from germany. Thanks in advanced Andreas -- Empfehlen Sie GMX DSL Ihren Freunden und Bekannten und wir belohnen Sie mit bis zu 50,- Euro! https://freundschaftswerbung.gmx.de