bug#52692: 27.2; wrong-type-argument in c-forward-decl-or-cast-1

bug#52692: 27.2; wrong-type-argument in c-forward-decl-or-cast-1

[Simon Schubert]

Invoking c-context-line-break leads to wrong-type-argument if used with
a custom type, but not when used with a struct. See example below:


typedef struct some_type_struct {
    int some_field;
} some_type;

void foo(some_type t) {
}

void test(void) {
    foo((struct some_type_struct){ // fine: (c-context-line-break)
    });
    foo((some_type){ // error: (c-context-line-break)
    });
}



In GNU Emacs 27.2 (build 1, x86_64-pc-linux-gnu, X toolkit, Xaw scroll 
bars)
of 2021-05-03 built on ernest
Repository revision: 930a410a9b054a61e004db3e0d35f1ff9b5f4796
Repository branch: master
Windowing system distributor 'The X.Org Foundation', version 11.0.12101001
System Description: Arch Linux

Recent messages:
Undo [2 times]
4 (#o4, #x4, ?\C-d)
Undo
Entering debugger...
Quit
user-error: No undo information in this buffer
Quit
Back to top level
Saving file /home/corecode/tmp/test.c...
Wrote /home/corecode/tmp/test.c

Configured using:
'configure --prefix=/usr --sysconfdir=/etc --libexecdir=/usr/lib
--localstatedir=/var --with-x-toolkit=lucid --with-xft --without-gconf
--without-gsettings --with-modules
'--program-transform-name=s/^ctags$/ctags.emacs/' 'CFLAGS=-march=x86-64
-mtune=generic -O2 -pipe -fno-plt -g
-fdebug-prefix-map=/home/corecode/.cache/yay/emacs-lucid/src=/usr/src/debug' 

CPPFLAGS=-D_FORTIFY_SOURCE=2
LDFLAGS=-Wl,-O1,--sort-common,--as-needed,-z,relro,-z,now'

Configured features:
XPM JPEG TIFF GIF PNG RSVG SOUND GPM DBUS GLIB NOTIFY INOTIFY ACL GNUTLS
LIBXML2 FREETYPE HARFBUZZ M17N_FLT LIBOTF XFT ZLIB TOOLKIT_SCROLL_BARS
LUCID X11 XDBE XIM MODULES THREADS LIBSYSTEMD JSON PDUMPER LCMS2 GMP

Important settings:
value of $LC_MONETARY: en_US.UTF-8
value of $LC_NUMERIC: en_US.UTF-8
value of $LC_TIME: en_GB.UTF-8
value of $LANG: en_DK.UTF-8
locale-coding-system: utf-8-unix

Major mode: C/*l

Minor modes in effect:
tooltip-mode: t
global-eldoc-mode: t
electric-indent-mode: t
mouse-wheel-mode: t
tool-bar-mode: t
menu-bar-mode: t
file-name-shadow-mode: t
global-font-lock-mode: t
font-lock-mode: t
blink-cursor-mode: t
auto-composition-mode: t
auto-encryption-mode: t
auto-compression-mode: t
line-number-mode: t
transient-mark-mode: t
abbrev-mode: t

Load-path shadows:
None found.

Features:
(shadow sort mail-extr emacsbug message rmc puny dired dired-loaddefs
format-spec rfc822 mml mml-sec password-cache epa derived epg epg-config
gnus-util rmail rmail-loaddefs text-property-search time-date subr-x
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mailheader sendmail rfc2047 rfc2045 ietf-drums mm-util mail-prsvr
mail-utils cl-print debug backtrace find-func misearch multi-isearch
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cc-menus cc-cmds cc-styles cc-align cc-engine cc-vars cc-defs
cl-loaddefs cl-lib tooltip eldoc electric uniquify ediff-hook vc-hooks
lisp-float-type mwheel term/x-win x-win term/common-win x-dnd tool-bar
dnd fontset image regexp-opt fringe tabulated-list replace newcomment
text-mode elisp-mode lisp-mode prog-mode register page tab-bar menu-bar
rfn-eshadow isearch timer select scroll-bar mouse jit-lock font-lock
syntax facemenu font-core term/tty-colors frame minibuffer cl-generic
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custom widget hashtable-print-readable backquote threads dbusbind
inotify lcms2 dynamic-setting font-render-setting x-toolkit x multi-tty
make-network-process emacs)

Memory information:
((conses 16 78411 9583)
(symbols 48 9636 1)
(strings 32 26037 2235)
(string-bytes 1 929397)
(vectors 16 14770)
(vector-slots 8 185362 12374)
(floats 8 40 30)
(intervals 56 682 8)
(buffers 1000 15))

bug#52692: 27.2; wrong-type-argument in c-forward-decl-or-cast-1

[Lars Ingebrigtsen]

Simon Schubert <2-gnu@0x2c.org> writes:

> Invoking c-context-line-break leads to wrong-type-argument if used with
> a custom type, but not when used with a struct. See example below:
>
> typedef struct some_type_struct {
>    int some_field;
> } some_type;
>
> void foo(some_type t) {
> }
>
> void test(void) {
>    foo((struct some_type_struct){ // fine: (c-context-line-break)
>    });
>    foo((some_type){ // error: (c-context-line-break)
>    });
> }
>
> In GNU Emacs 27.2 (build 1, x86_64-pc-linux-gnu, X toolkit, Xaw scroll
> bars)

I can reproduce this in Emacs 27.2, but not in Emacs 28, so it seems
like this problem is fixed for the next Emacs release, and I'm therefore
closing this bug report.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no