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X-OriginatorOrg: de.bosch.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 06 Jan 2026 08:48:47.8341 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 0571a298-e95d-4126-a96a-08de4d006857 X-MS-Exchange-CrossTenant-Id: 0ae51e19-07c8-4e4b-bb6d-648ee58410f4 X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=0ae51e19-07c8-4e4b-bb6d-648ee58410f4;Ip=[139.15.153.205];Helo=[eop.bosch-org.com] X-MS-Exchange-CrossTenant-AuthSource: AM3PEPF00009BA1.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: AM0PR10MB3714 Am 1/5/2026 um 11:44 AM schrieb Alice Ryhl: > On 32-bit ARM, you may encounter linker errors such as this one: > > ld.lld: error: undefined symbol: _find_next_zero_bit > >>> referenced by rust_binder_main.43196037ba7bcee1-cgu.0 > >>> drivers/android/binder/rust_binder_main.o:(::insert_or_update_handle) in archive vmlinux.a > >>> referenced by rust_binder_main.43196037ba7bcee1-cgu.0 > >>> drivers/android/binder/rust_binder_main.o:(::insert_or_update_handle) in archive vmlinux.a > > This error occurs because even though the functions are declared by > include/linux/find.h, the definition is #ifdef'd out on 32-bit ARM. This > is because arch/arm/include/asm/bitops.h contains: > > #define find_first_zero_bit(p,sz) _find_first_zero_bit_le(p,sz) > #define find_next_zero_bit(p,sz,off) _find_next_zero_bit_le(p,sz,off) > #define find_first_bit(p,sz) _find_first_bit_le(p,sz) > #define find_next_bit(p,sz,off) _find_next_bit_le(p,sz,off) > > And the underscore-prefixed function is conditional on #ifndef of the > non-underscore-prefixed name, but the declaration in find.h is *not* > conditional on that #ifndef. > > To fix the linker error, we ensure that the symbols in question exist > when compiling Rust code. We do this by definining them in rust/helpers/ Just a quite minor nit: typo: definining -> defining Dirk