Subject: 25.1; byte-compile-error-on-warn doesn't treat all warnings as errors

From: Philipp <[email-masked]>
Date: Sat, 03 Sep 2016 19:40:05 +0200

Create a file /tmp/a.el with the following content:

(funcall '(lambda ()))

Then run

$ emacs -batch -Q -eval '(setq byte-compile-error-on-warn t)' -f batch-byte-compile /tmp/a.el ; echo $?

In toplevel form:
/tmp/a.el:1:1:Warning: (lambda nil ...) quoted with ' rather than with #'
0

Expected behavior: The warning is treated as an error because
byte-compile-error-on-warn is non-nil.

Actual behavior: The warning is not treated as an error.

This is because some warnings use byte-compile-log-warning instead of
byte-compile-warn.  In this case, macroexp--warn-and-return is the
culprit.  Probably byte-compile-log-warning should be made internal to
bytecomp.el, and never be called except from byte-compile-warn and
byte-compile-report-error.

In GNU Emacs 25.1.3 (x86_64-unknown-linux-gnu, GTK+ Version 3.10.8)
 of 2016-09-03 built on unknown
Repository revision: 803ad6f7e7a9c6bcf8a6cbf8eaad17501b114a33
Windowing system distributor 'The X.Org Foundation', version 11.0.11702000
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Memory information:
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 (miscs 40 327 168)
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 (string-bytes 1 636109)
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