With the IRA_COVER_CLASSES in cris.h changed as follows (exposing one of the GENERAL_REGS that has special properties as a singleton class), build fails compiling libgcc:
/home/hp/combw/crisv32-obj/./gcc/xgcc -B/home/hp/combw/crisv32-obj/./gcc/ -nostdinc -B/home/hp/combw/crisv32-obj/crisv32-elf/newlib/ -isystem /home/hp/combw/crisv32-obj/crisv32-elf/newlib/targ-include -isystem /home/hp/combw/combined/newlib/libc/include -B/home/hp/combw/crisv32-obj/crisv32-elf/libgloss/cris -L/home/hp/combw/crisv32-obj/crisv32-elf/libgloss/libnosys -L/home/hp/combw/combined/libgloss/cris -B/tmp/reg-crisv32/crisv32-elf/bin/ -B/tmp/reg-crisv32/crisv32-elf/lib/ -isystem /tmp/reg-crisv32/crisv32-elf/include -isystem /tmp/reg-crisv32/crisv32-elf/sys-include -L/home/hp/combw/crisv32-obj/./ld -g -O2 -O2 -g -O2 -DIN_GCC -DCROSS_DIRECTORY_STRUCTURE -W -Wall -Wwrite-strings -Wstrict-prototypes -Wmissing-prototypes -Wcast-qual -Wold-style-definition -isystem ./include -g -DIN_LIBGCC2 -D__GCC_FLOAT_NOT_NEEDED -Dinhibit_libc -I. -I. -I../.././gcc -I/home/hp/combw/combined/libgcc -I/home/hp/combw/combined/libgcc/. -I/home/hp/combw/combined/libgcc/../gcc -I/home/hp/combw/combined/libgcc/../include -DHAVE_CC_TLS -o _muldi3.o -MT _muldi3.o -MD -MP -MF _muldi3.dep -DL_muldi3 -c /home/hp/combw/combined/libgcc/../gcc/libgcc2.c \ /home/hp/combw/combined/libgcc/../gcc/libgcc2.c: In function '__muldi3': /home/hp/combw/combined/libgcc/../gcc/libgcc2.c:566: internal compiler error: in process_bb_node_lives, at ira-lives.c:677 Index: gcc/config/cris/cris.h =================================================================== --- gcc/config/cris/cris.h (revision 141074) +++ gcc/config/cris/cris.h (working copy) @@ -597,7 +597,7 @@ #define INDEX_REG_CLASS GENERAL_REGS -#define IRA_COVER_CLASSES { GENERAL_REGS, SPECIAL_REGS, LIM_REG_CLASSES } +#define IRA_COVER_CLASSES { ACR_REGS, GENNONACR_REGS, SPECIAL_REGS, LIM_REG_CLASSES } #define REG_CLASS_FROM_LETTER(C) \ ( \ Preprocessed libgcc2.i to be attached. -- Summary: assert with IRA_COVER_CLASSES with singleton Product: gcc Version: 4.4.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: middle-end AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: hp at gcc dot gnu dot org GCC host triplet: x86_64-unknown-linux-gnu GCC target triplet: crisv32-axis-elf http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37813