From: Thomas Hellström Date: Fri, 5 Jun 2026 09:33:05 +0000 (+0200) Subject: drm/xe/rtp: Fix build error with clang < 21 and non-const initializers X-Git-Tag: v7.2-rc2~10^2~1^2~17 X-Git-Url: http://git.ipfire.org/gitweb/?a=commitdiff_plain;h=61596826b89af9dc20a53bae79b2b41e2bdc1fb5;p=thirdparty%2Flinux.git drm/xe/rtp: Fix build error with clang < 21 and non-const initializers Clang < 21 treats const-qualified compound literals at function scope as having static storage duration, which requires all initializer elements to be compile-time constants. When xe_hw_engine.c initializes a local struct xe_rtp_table_sr using XE_RTP_TABLE_SR(), the compound literals in XE_RTP_TABLE_SR end up containing runtime values (e.g. blit_cctl_val derived from gt->mocs.uc_index), triggering: xe_hw_engine.c:361: error: initializer element is not a compile-time constant xe_hw_engine.c:416: error: initializer element is not a compile-time constant ARRAY_SIZE() cannot be used as a replacement because it expands through __must_be_array() -> __BUILD_BUG_ON_ZERO_MSG() -> _Static_assert inside sizeof(struct{}), which clang < 21 also rejects in the same context. Replace ARRAY_SIZE() with an open-coded sizeof(arr)/sizeof(elem) in XE_RTP_TABLE_SR and XE_RTP_TABLE to avoid both issues. Fixes: e23fafb8594e ("drm/xe/rtp: Add struct types for RTP tables") Cc: Matt Roper Cc: Gustavo Sousa Cc: Violet Monti Cc: Matthew Brost Cc: Thomas Hellström Cc: Rodrigo Vivi Cc: Ashutosh Dixit Cc: intel-xe@lists.freedesktop.org Reported-by: Mark Brown Closes: https://lore.kernel.org/intel-xe/bfb0dee8-b243-47ba-a89d-71472b0d51c5@sirena.org.uk/ Assisted-by: GitHub_Copilot:claude-sonnet-4.6 Signed-off-by: Thomas Hellström Reviewed-by: Gustavo Sousa Link: https://patch.msgid.link/20260605093305.110598-1-thomas.hellstrom@linux.intel.com (cherry picked from commit a57011eff45e7265dc42a7adad68b84605d8f828) Signed-off-by: Thomas Hellström --- diff --git a/drivers/gpu/drm/xe/xe_rtp.h b/drivers/gpu/drm/xe/xe_rtp.h index 4e3cfd69f922..2cc65053cd07 100644 --- a/drivers/gpu/drm/xe/xe_rtp.h +++ b/drivers/gpu/drm/xe/xe_rtp.h @@ -461,14 +461,22 @@ struct xe_reg_sr; XE_RTP_PASTE_FOREACH(ACTION_, COMMA, (__VA_ARGS__)) \ } +/* + * Note: ARRAY_SIZE() cannot be used here because it expands through + * __must_be_array() -> __BUILD_BUG_ON_ZERO_MSG() -> _Static_assert inside + * sizeof(struct{}), which clang < 21 rejects when the compound literal + * contains non-compile-time-constant initializers. + */ #define XE_RTP_TABLE_SR(...) { \ .entries = (const struct xe_rtp_entry_sr[]){__VA_ARGS__}, \ - .n_entries = ARRAY_SIZE(((const struct xe_rtp_entry_sr[]){__VA_ARGS__})), \ + .n_entries = sizeof((const struct xe_rtp_entry_sr[]){__VA_ARGS__}) / \ + sizeof(struct xe_rtp_entry_sr), \ } #define XE_RTP_TABLE(...) { \ .entries = (const struct xe_rtp_entry[]){__VA_ARGS__}, \ - .n_entries = ARRAY_SIZE(((const struct xe_rtp_entry[]){__VA_ARGS__})), \ + .n_entries = sizeof((const struct xe_rtp_entry[]){__VA_ARGS__}) / \ + sizeof(struct xe_rtp_entry), \ } #define XE_RTP_PROCESS_CTX_INITIALIZER(arg__) _Generic((arg__), \