zsh/system's $errnos empty with recent gcc

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• From: Stephane Chazelas <stephane.chazelas@xxxxxxxxx>
• To: zsh-workers@xxxxxxx
• Subject: zsh/system's $errnos empty with recent gcc
• Date: Wed, 7 Sep 2016 10:28:41 +0100
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At least on Ubuntu 16.04 and Debian unstable, $errnos comes out empty. It's down to the generation of errnames.c. Part of that involves calling $CPP on an awk generated file, and post-process $CPP's output with a second awk script. It looks like the $CPP output has changed recently. I had a very similar issue when compiling pdksh, passing the -P (to remove the #<n> line numbers) fixed it there and it does fix it for zsh as well. I don't know how portable -P is (it is for gcc anyway), but it would make sense to use it when available here. That probably calls for a new autoconf check. Alternatively, we could modify the awk script to take that new gcc output into account. This: #include <errno.h> XXNAMES XXENOSYS ENOSYS going through gcc -E now gives: [...] # 2 "a.c" XXNAMES XXENOSYS # 2 "a.c" 3 4 38 While before it would give: [...] # 2 "a.c" 2 XXNAMES XXENOSYS 38 With gcc -E -P, it gives: [...] XXNAMES XXENOSYS 38 Like before. which is the format expected by errnames2.awk. -- Stephane 

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  • Re: zsh/system's $errnos empty with recent gcc
    • From: Peter Stephenson