[PATCH] ALSA: hda/ca0132: work around clang -Wuninitialized warning

From: Arnd Bergmann
Date: Fri Mar 22 2019 - 10:08:15 EST


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@xxxxxxxx>
---
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