bug#16724: 24.3.50; Buffer *Backtrace* loses text scaling - unusable

bug#16724: 24.3.50; Buffer *Backtrace* loses text scaling - unusable

[Drew Adams]

emacs -Q

You want to use the debugger on a function, and you want to see as much
as possible of each line in the debugger.  So you use debug-on-entry,
and then, after buffer *Backtrace* is displayed, you use C-mouse-1 and
choose Decrease Buffer Text Size.

You hit `d', and immediately buffer *Backtrace* loses the text scaling
you just set for it.

In reality, *Backtrace* might have be killed and re-created (or
whatever), but from a _user_ point of view, s?he is still in the same
buffer, and text scaling is broken.  To get the effect expected, s?he
has to repeat the C-mouse-1 and choosing to decrease the text size,
*each* time s?he hits a key (e.g., `d').



In GNU Emacs 24.3.50.1 (i686-pc-mingw32)
 of 2014-02-06 on ODIEONE
Bzr revision: 116299 rgm@gnu.org-20140207032552-3ycw6hai2zl7yynq
Windowing system distributor `Microsoft Corp.', version 6.1.7601
Configured using:
 `configure --prefix=/c/Devel/emacs/binary --enable-checking=yes,glyphs
 'CFLAGS=-O0 -g3' LDFLAGS=-Lc:/Devel/emacs/lib
 CPPFLAGS=-Ic:/Devel/emacs/include'

bug#16724: 24.3.50; Buffer *Backtrace* loses text scaling - unusable

[Stefan Monnier]

> You hit `d', and immediately buffer *Backtrace* loses the text scaling
> you just set for it.

Indeed, the buffer's major mode is re-applied every time, and it's
a mistake.  Patch welcome,


        Stefan