Hi all,

The byte-compiler doesn't always report the right line and column numbers. For example for the following program in test.el:

(defun test ()
  (let (a))
  a)

Running M-x byte-compile-file RET test.el RET yields:

> Compiling file /home/clement/test.el at Fri Jan  1 10:48:41 2016
>
> In test:
> test.el:2:9:Warning: reference to free variable ‘a’

The correct warning would be

> test.el:3:2:Warning: reference to free variable ‘a’

Note that the following program gives the right error:

(defun test ()
  (let (b))
  a)

> test.el:3:3:Warning: reference to free variable ‘a’

Although one might argue that it should be

> test.el:3:2:Warning: reference to free variable ‘a’

(that is, column 2, not 3) given that Emacs starts counting columns at 0.

Cheers,
Clément.

In GNU Emacs 25.0.50.8 (x86_64-unknown-linux-gnu, GTK+ Version 3.10.8)
 of 2015-12-29 built on clem-w50-mint
Repository revision: a21bb238ce7bcc9c13a9cf66db77918304daa2fc
Windowing system distributor 'The X.Org Foundation', version 11.0.11501000
System Description:	Linux Mint 17.2 Rafaela

Configured features:
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NOTIFY ACL LIBSELINUX GNUTLS LIBXML2 FREETYPE M17N_FLT LIBOTF XFT ZLIB
TOOLKIT_SCROLL_BARS GTK3 X11

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Memory information:
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