[FIX] Silence unused-but-set variable warning in zvbi decoder

[AS-pngg]

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{pull request content here}
This PR fixes a compiler warning (-Wunused-but-set-variable) by explicitly
marking an intentionally unused local variable in zvbi/decoder.c.

There are no functional changes.

[cfsmp3]

If it's unused why not just remove it?
Clean up is fine, but just hiding warnings by adding unexplainable code is not a good idea :-)

[AS-pngg]

If it's unused why not just remove it? Clean up is fine, but just hiding warnings by adding unexplainable code is not a good idea :-)

Thanks for pointing this out.

I initially considered removing the variable, but it is still required for the assignment call (vbi3_raw_decoder_set_sampling_par(...)) where the side effect is needed, even though the returned value is not used later.

I agree that removing unused code is preferable where possible — if there’s a better approach you’d recommend here (e.g., refactoring the call or handling the return value differently), I’m happy to update the patch.

[cfsmp3]

Instead of silencing the warning with (void), please remove the variable entirely:

// Remove this line:
vbi_service_set service_set;

// And change this:
service_set = vbi3_raw_decoder_set_sampling_par(rd3, (vbi_sampling_par *)rd, /* strict */ 0);
(void)service_set;

// To just:
vbi3_raw_decoder_set_sampling_par(rd3, (vbi_sampling_par *)rd, /* strict */ 0);

The function is called for its side effects; there's no need to capture the return value if we're not using it.

[AS-pngg]

Done I’ve removed the unused variable entirely and updated the call to rely only on the function’s side effects, as suggested.
Thanks for the clear explanation!

[ccextractor-bot]

CCExtractor CI platform finished running the test files on linux. Below is a summary of the test results, when compared to test for commit 64ce4ac...:

Report Name	Tests Passed
Broken	13/13
CEA-708	14/14
DVB	7/7
DVD	3/3
DVR-MS	2/2
General	25/27
Hardsubx	1/1
Hauppage	3/3
MP4	3/3
NoCC	10/10
Options	81/86
Teletext	21/21
WTV	13/13
XDS	34/34

Your PR breaks these cases:

• ccextractor --autoprogram --out=ttxt --latin1 --ucla dab1c1bd65...
• ccextractor --out=srt --latin1 --autoprogram 29e5ffd34b...
• ccextractor --startcreditstext "CCextractor Start crdit Testing" c4dd893cb9...
• ccextractor --startcreditsnotbefore 1 --startcreditstext "CCextractor Start crdit Testing" c4dd893cb9...
• ccextractor --startcreditsnotafter 2 --startcreditstext "CCextractor Start crdit Testing" c4dd893cb9...
• ccextractor --startcreditsforatleast 1 --startcreditstext "CCextractor Start crdit Testing" c4dd893cb9...
• ccextractor --startcreditsforatmost 2 --startcreditstext "CCextractor Start crdit Testing" c4dd893cb9...

It seems that not all tests were passed completely. This is an indication that the output of some files is not as expected (but might be according to you).

Check the result page for more info.

[ccextractor-bot]

CCExtractor CI platform finished running the test files on windows. Below is a summary of the test results, when compared to test for commit 64ce4ac...:

Report Name	Tests Passed
Broken	13/13
CEA-708	14/14
DVB	7/7
DVD	3/3
DVR-MS	2/2
General	27/27
Hardsubx	1/1
Hauppage	3/3
MP4	3/3
NoCC	10/10
Options	86/86
Teletext	21/21
WTV	13/13
XDS	34/34

Congratulations: Merging this PR would fix the following tests:

• ccextractor --autoprogram --out=srt --latin1 --quant 0 85271be4d2..., Last passed: Never
• ccextractor --autoprogram --out=ttxt --latin1 --ucla dab1c1bd65..., Last passed: Never
• ccextractor --out=srt --latin1 --autoprogram 29e5ffd34b..., Last passed: Never
• ccextractor --out=spupng c83f765c66..., Last passed: Never
• ccextractor --startcreditstext "CCextractor Start crdit Testing" c4dd893cb9..., Last passed: Never
• ccextractor --startcreditsnotbefore 1 --startcreditstext "CCextractor Start crdit Testing" c4dd893cb9..., Last passed: Never
• ccextractor --startcreditsnotafter 2 --startcreditstext "CCextractor Start crdit Testing" c4dd893cb9..., Last passed: Never
• ccextractor --startcreditsforatleast 1 --startcreditstext "CCextractor Start crdit Testing" c4dd893cb9..., Last passed: Never
• ccextractor --startcreditsforatmost 2 --startcreditstext "CCextractor Start crdit Testing" c4dd893cb9..., Last passed: Never

All tests passed completely.

Check the result page for more info.