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From: "terra at gnome dot org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug preprocessor/108108] "gcc -MM" fails to list all dependencies
Date: Wed, 14 Dec 2022 18:40:06 +0000	[thread overview]
Message-ID: <bug-108108-4-lo6ceZrJJ7@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-108108-4@http.gcc.gnu.org/bugzilla/>

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108108

--- Comment #4 from M Welinder <terra at gnome dot org> ---
> Since it was not read again, the file is not considered included ...

It must have been read -- how else could gcc decide it was the same?

# strace -f gcc -MM c.c 2>&1 >Makefile  | grep 'open.*\.h' | grep -v /
[pid 30494] openat(AT_FDCWD, "a.h", O_RDONLY|O_NOCTTY) = 3
[pid 30494] openat(AT_FDCWD, "b.h", O_RDONLY|O_NOCTTY) = 3

If it was necessary to open that file, then it's a dependency.


> Really #pragma once should just emit a warning just like #import does ...

I hear you, :-)

      parent reply	other threads:[~2022-12-14 18:40 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-12-14 18:01 [Bug other/108108] New: " terra at gnome dot org
2022-12-14 18:05 ` [Bug preprocessor/108108] " pinskia at gcc dot gnu.org
2022-12-14 18:11 ` pinskia at gcc dot gnu.org
2022-12-14 18:11 ` pinskia at gcc dot gnu.org
2022-12-14 18:40 ` terra at gnome dot org [this message]

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