[PATCH][next] x86/fpu: Replace zero-length array with flexible-array member

From: Gustavo A. R. Silva
Date: Mon Jan 09 2023 - 20:41:14 EST


Zero-length arrays are deprecated[1] and we are moving towards
adopting C99 flexible-array members instead. So, replace zero-length
array declaration in struct xregs_state with flex-array member.

This helps with the ongoing efforts to tighten the FORTIFY_SOURCE
routines on memcpy() and help us make progress towards globally
enabling -fstrict-flex-arrays=3 [2].

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#zero-length-and-one-element-arrays [1]
Link: https://gcc.gnu.org/pipermail/gcc-patches/2022-October/602902.html [2]
Link: https://github.com/KSPP/linux/issues/78
Signed-off-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>
---
arch/x86/include/asm/fpu/types.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/fpu/types.h b/arch/x86/include/asm/fpu/types.h
index eb7cd1139d97..7f6d858ff47a 100644
--- a/arch/x86/include/asm/fpu/types.h
+++ b/arch/x86/include/asm/fpu/types.h
@@ -321,7 +321,7 @@ struct xstate_header {
struct xregs_state {
struct fxregs_state i387;
struct xstate_header header;
- u8 extended_state_area[0];
+ u8 extended_state_area[];
} __attribute__ ((packed, aligned (64)));

/*
--
2.34.1