Even though it practically should never happen, but just in case, and
for silencing the analyzer, add an extra check here (which doesn't
cost us much).
| ../render/picture.c: In function ‘cpAlphaMap’:
| ../render/picture.c:1002:30: warning: dereference of NULL ‘screen’ [CWE-476] [-Wanalyzer-null-dereference]
| 1002 | id = res->info[screen->myNum].id;
| | ~~~~~~^~~~~~~
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
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