On Fri, Mar 22, 2019 at 03:06:28PM +0100, Arnd Bergmann wrote:
When CONFIG_PCI is disabled, clang gets confused about the control flow of the switch() statement always ending up in the default case, and warns:
sound/pci/hda/patch_ca0132.c:7558:6: error: variable 'fw_entry' is used uninitialized whenever 'if' condition is false [-Werror,-Wsometimes-uninitialized] if (!spec->alt_firmware_present) { ^~~~~~~~~~~~~~~~~~~~~~~~~~~ sound/pci/hda/patch_ca0132.c:7565:42: note: uninitialized use occurs here dsp_os_image = (struct dsp_image_seg *)(fw_entry->data); ^~~~~~~~ sound/pci/hda/patch_ca0132.c:7558:2: note: remove the 'if' if its condition is always true if (!spec->alt_firmware_present) { ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ sound/pci/hda/patch_ca0132.c:7521:33: note: initialize the variable 'fw_entry' to silence this warning const struct firmware *fw_entry; ^ = NULL
Adding an explicit check for CONFIG_PCI avoids the issue. Unfortunately this is not very intuitive here.
Link: https://bugs.llvm.org/show_bug.cgi?id=41197#c1 Signed-off-by: Arnd Bergmann arnd@arndb.de
Reviewed-by: Nathan Chancellor natechancellor@gmail.com
Any suggestions for other workarounds appreciated. If you can think of a better fix, please treat this as a reported-by:
sound/pci/hda/patch_ca0132.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/sound/pci/hda/patch_ca0132.c b/sound/pci/hda/patch_ca0132.c index 29882bda7632..415b16b7db70 100644 --- a/sound/pci/hda/patch_ca0132.c +++ b/sound/pci/hda/patch_ca0132.c @@ -7555,7 +7555,7 @@ static bool ca0132_download_dsp_images(struct hda_codec *codec) * Use default ctefx.bin if no alt firmware is detected, or if none * exists for your particular codec. */
- if (!spec->alt_firmware_present) {
- if (!IS_ENABLED(CONFIG_PCI) || !spec->alt_firmware_present) { codec_dbg(codec, "Default firmware selected."); if (request_firmware(&fw_entry, EFX_FILE, codec->card->dev) != 0)
-- 2.20.0