I got the following compile error when trying to compile Linux kernel 2.6.22-rc6-mm1 with a recent gcc SVN snapshot:
$ /usr/local/DIR/gcc-svn20070715/bin/gcc -Wp,-MD,mm/.page_alloc.o.d -nostdinc -isystem /usr/local/DIR/gcc-svn20070715/lib/gcc/i686-pc-linux-gnu/4.3.0/include -D__KERNEL__ -Iinclude -include include/linux/autoconf.h -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs -fno-strict-aliasing -fno-common -Werror-implicit-function-declaration -Werror-implicit-function-declaration -Os -pipe -msoft-float -mregparm=3 -freg-struct-return -mpreferred-stack-boundary=2 -march=athlon -ffreestanding -maccumulate-outgoing-args -DCONFIG_AS_CFI=1 -DCONFIG_AS_CFI_SIGNAL_FRAME=1 -Iinclude/asm-i386/mach-generic -Iinclude/asm-i386/mach-default -fno-omit-frame-pointer -fno-optimize-sibling-calls -fasynchronous-unwind-tables -fno-stack-protector -Wdeclaration-after-statement -Wno-pointer-sign -D"KBUILD_STR(s)=#s" -D"KBUILD_BASENAME=KBUILD_STR(page_alloc)" -D"KBUILD_MODNAME=KBUILD_STR(page_alloc)" -c -o mm/page_alloc.o mm/page_alloc.c: In function â__build_all_zonelistsâ: mm/page_alloc.c:2381: error: found real variable when subvariables should have appeared while verifying SSA_NAME used_mask_87 in statement # node_2_cpu_mask_468 = VDEF <node_2_cpu_mask_640> # node_data_469 = VDEF <node_data_644> # zone_reclaim_mode_470 = VDEF <zone_reclaim_mode_648> # policy_zone_471 = VDEF <policy_zone_652> # node_load_472 = VDEF <node_load_656> # node_order_473 = VDEF <node_order_660> # used_mask_87 = VDEF <used_mask_564> # tmp_474 = VDEF <tmp_664> # SFT.3392_475 = VDEF <SFT.3392_668> # SFT.3393_476 = VDEF <SFT.3393_672> # SMT.3398_196 = VDEF <SMT.3398_251> D.24412_7->node_zonelists[i.600_23].zlcache_ptr = zlc_26; ... -- Summary: [4.3 Regression] error: found real variable when subvariables should have appeared Product: gcc Version: 4.3.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: bunk at stusta dot de GCC build triplet: i686-pc-linux-gnu GCC host triplet: i686-pc-linux-gnu GCC target triplet: i686-pc-linux-gnu http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32772