Hi I've tested gcc-4.4 with the current developer kernel 2.6.26-rc4 and got the following compile error:
... Setup is 12236 bytes (padded to 12288 bytes). System is 2521 kB CRC 735d1682 Kernel: arch/x86/boot/bzImage is ready (#62) Building modules, stage 2. MODPOST 222 modules ERROR: "____ilog2_NaN" [drivers/usb/core/usbcore.ko] undefined! make[1]: *** [__modpost] Error 1 make: *** [modules] Error 2 This can be avoided when switching on the OPTIMIZE_SIZE kconfig option which in fact replaces the standard -O2 option with -Os, so I think there must be something wrong in what -O2 does. This happens only with gcc-4.4 not with gcc-4.3 and before (I've also tested gcc-4.1). The latest gcc-4.4 version I tested was 20080526. I compiled gcc without any options to ./configure. I'll try to attach my config file so you might be able to reproduce the error. This has been reported to lkml. The discussion can be read here: http://lkml.org/lkml/2008/5/25/169. Thanks Mirco -- Summary: [Regression] compile error in linux-kernel 2.6.26-rc4 with -O2 Product: gcc Version: 4.4.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: mt-ml at gmx dot de GCC build triplet: none GCC host triplet: ubuntu linux 8.10 (dev) GCC target triplet: x86_64 http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36359
