video: driver: copy struct v4l2_format by assignment#125
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GCC 16.1 with -Wstringop-overread (turned into an error by the driver's own -Werror) rejects the byte-wise copies of a whole struct v4l2_format: msm_venc.c:1327:9: error: 'memcpy' reading 208 bytes from a region of size 0 [-Werror=stringop-overread] note: source object is likely at address zero After msm_venc_s_fmt_input() is inlined into msm_venc_s_fmt(), the compiler's value-range analysis mis-judges the source object (&inst->fmts[INPUT_PORT]) as a zero-sized region at address zero and rejects the memcpy(). The source is a regular member of struct msm_vidc_inst and is never NULL, so this is a false positive, but it breaks the build for newer toolchains. Copy the structures with a plain aggregate assignment instead of memcpy(). The assignment is a by-value copy of the whole structure - it copies the entire object, including the embedded union, exactly as the old memcpy(..., sizeof(struct v4l2_format)) did. It lets the compiler derive the size from the type and is not subject to the string/memory builtin diagnostics, so it both fixes the build and is more idiomatic. No functional change intended. Assisted-by: Claude:claude-opus-4.8 Signed-off-by: Ricardo Salveti <ricardo.salveti@oss.qualcomm.com>
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GCC 16.1 with -Wstringop-overread (turned into an error by the driver's own -Werror) rejects the byte-wise copies of a whole struct v4l2_format:
msm_venc.c:1327:9: error: 'memcpy' reading 208 bytes from a region
of size 0 [-Werror=stringop-overread]
note: source object is likely at address zero
After msm_venc_s_fmt_input() is inlined into msm_venc_s_fmt(), the compiler's value-range analysis mis-judges the source object (&inst->fmts[INPUT_PORT]) as a zero-sized region at address zero and rejects the memcpy(). The source is a regular member of struct msm_vidc_inst and is never NULL, so this is a false positive, but it breaks the build for newer toolchains.
Copy the structures with a plain aggregate assignment instead of memcpy(). The assignment is a by-value copy of the whole structure - it copies the entire object, including the embedded union, exactly as the old memcpy(..., sizeof(struct v4l2_format)) did. It lets the compiler derive the size from the type and is not subject to the string/memory builtin diagnostics, so it both fixes the build and is more idiomatic.
No functional change intended.
Assisted-by: Claude:claude-opus-4.8