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Date: Sun, 24 Jul 2022 14:40:48 +0200 (CEST)
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Subject: Empty element in CPATH variable
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Hi everyone,

the documentation explicitly states that empty elements in CPATH and other variables that control header search path can appear at thebeginning or end of a list. 

https://gcc.gnu.org/onlinedocs/cpp/Environment-Variables.html

But in reality nothing stops you from putting empty element anywhere in the list.

export CPATH="$HOME/include::$HOME/project/include"

cpp -nostdinc /dev/null -o /dev/null -v 2>&1 | awk '/#include/,/End/'

#include "..." search starts here:
#include <...> search starts here:
/root/include
.
/root/project/include
End of search list.

In general I would not consider it to be a bug, but the accent on the beginning and end of the list makes me wonder it it is a bug or a bad description.

Thanks,
Andrii