[PATCH] [next] drm/radeon: Replace 1-element arrays with flexible-array members

From: Paulo Miguel Almeida
Date: Fri Dec 09 2022 - 03:24:29 EST


One-element arrays are deprecated, and we are replacing them with
flexible array members instead. So, replace one-element array with
flexible-array member in structs _ATOM_DISPLAY_OBJECT_PATH,
_ATOM_DISPLAY_OBJECT_PATH_TABLE, _ATOM_OBJECT_TABLE, GOP_VBIOS_CONTENT
_ATOM_GPIO_VOLTAGE_OBJECT_V3 and refactor the rest of the code accordingly.

It's worth mentioning that doing a build before/after this patch
results in no binary output differences.

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 [1].

Link: https://github.com/KSPP/linux/issues/79
Link: https://github.com/KSPP/linux/issues/239
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101836 [1]

Signed-off-by: Paulo Miguel Almeida <paulo.miguel.almeida.rodenas@xxxxxxxxx>
---
Notes for the maintainer:

- These are all fake-flexible arrays with references in source code for
the radeon driver. Given the way they are used, no change to *.c files
were required.
---
drivers/gpu/drm/radeon/atombios.h | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/radeon/atombios.h b/drivers/gpu/drm/radeon/atombios.h
index 235e59b547a1..8a6621f1e82c 100644
--- a/drivers/gpu/drm/radeon/atombios.h
+++ b/drivers/gpu/drm/radeon/atombios.h
@@ -4020,7 +4020,7 @@ typedef struct _ATOM_DISPLAY_OBJECT_PATH
USHORT usSize; //the size of ATOM_DISPLAY_OBJECT_PATH
USHORT usConnObjectId; //Connector Object ID
USHORT usGPUObjectId; //GPU ID
- USHORT usGraphicObjIds[1]; //1st Encoder Obj source from GPU to last Graphic Obj destinate to connector.
+ USHORT usGraphicObjIds[]; //1st Encoder Obj source from GPU to last Graphic Obj destinate to connector.
}ATOM_DISPLAY_OBJECT_PATH;

typedef struct _ATOM_DISPLAY_EXTERNAL_OBJECT_PATH
@@ -4037,7 +4037,7 @@ typedef struct _ATOM_DISPLAY_OBJECT_PATH_TABLE
UCHAR ucNumOfDispPath;
UCHAR ucVersion;
UCHAR ucPadding[2];
- ATOM_DISPLAY_OBJECT_PATH asDispPath[1];
+ ATOM_DISPLAY_OBJECT_PATH asDispPath[];
}ATOM_DISPLAY_OBJECT_PATH_TABLE;


@@ -4053,7 +4053,7 @@ typedef struct _ATOM_OBJECT_TABLE //Above 4 object table
{
UCHAR ucNumberOfObjects;
UCHAR ucPadding[3];
- ATOM_OBJECT asObjects[1];
+ ATOM_OBJECT asObjects[];
}ATOM_OBJECT_TABLE;

typedef struct _ATOM_SRC_DST_TABLE_FOR_ONE_OBJECT //usSrcDstTableOffset pointing to this structure
@@ -4615,7 +4615,7 @@ typedef struct _ATOM_GPIO_VOLTAGE_OBJECT_V3
UCHAR ucPhaseDelay; // phase delay in unit of micro second
UCHAR ucReserved;
ULONG ulGpioMaskVal; // GPIO Mask value
- VOLTAGE_LUT_ENTRY_V2 asVolGpioLut[1];
+ VOLTAGE_LUT_ENTRY_V2 asVolGpioLut[];
}ATOM_GPIO_VOLTAGE_OBJECT_V3;

typedef struct _ATOM_LEAKAGE_VOLTAGE_OBJECT_V3
@@ -7964,7 +7964,7 @@ typedef struct {

typedef struct {
VFCT_IMAGE_HEADER VbiosHeader;
- UCHAR VbiosContent[1];
+ UCHAR VbiosContent[];
}GOP_VBIOS_CONTENT;

typedef struct {
--
2.38.1