Re: [OE-core] [PATCH] gcc: Fix tm.h plugin header

On Tue, 2021-12-21 at 11:56 +0000, Andrei Gherzan wrote:

On Mon, 20 Dec 2021, at 01:39, Bernhard Rosenkränzer via
lists.openembedded.org wrote:

quoted

On Thu, Dec 9, 2021 at 07:40 PM, Andrei Gherzan wrote:
 

quoted

On Thu, 9 Dec 2021, at 16:40, Khem Raj wrote:
 

quoted

On Thu, Dec 9, 2021 at 7:40 AM Andrei Gherzan [off-list ref]
wrote:
 

quoted

From: Andrei Gherzan <redacted>

On x86-64, tm.h (needed to build gcc plugins) tries to include
config/i386/linux64.h, which isn't installed. Fortunately it also
isn't
used, so simply removing the include statement is an ok fix.

is it due to multilib support ? if so we might be ok since we may not
be using it
but really it will be good to check it with multilib builds of
x86_64/x86

I don't think it is related to multilib but I'll give multilib a try. In
my case, the issue was revealed when compiling a kernel plugin config. I
can't remember right now which one but I can replicate it for logs.

Hi,
I've had a closer look at the problem, and can confirm the patch doesn't
break even in multilib setups.

The problem is that in a non-multilib setup, the config/i386/linux64.h
header is not generated, but tm.h tries to include it nevertheless, causing
any gcc plugin that #includes tm.h (such as all the gcc plugins in the
kernel -- tm.h is included by scripts/gcc-plugins/gcc-common.h) to fail to
build.
An alternative fix would be adding
mkdir -p ${D}${libdir}/gcc/${TARGET_SYS}/${BINV}/plugin/include/config/i386
touch ${D}${libdir}/gcc/${TARGET_SYS}/${BINV}/plugin/include/config/i386/lin
ux64.h
(creating the file if it isn't there) instead. This would make sure that in
cases where config/i386/linux64.h does exist, it doesn't get removed from
tm.h (potentially fixing plugins that reference any of the #defines in
i386/linux64.h without including the file manually -- but I have yet to see
any such plugin).

I will try to get a better fix (not adding the include statement to tm.h in
the first place rather than having to remove it later in install scripts)
upstream, but in the mean time, the patch fixes our builds before the better
fix is ready/applied.

Ping on this patch. Any chance we can pull it in as a first iteration of the
solution?

I don't like sed in this context as if the code changes, it silently stops
working and we struggle to know what broke or whether we need to fix it. We
don't have any test case.

Given all that, the touch of the file is a neater solution as it is more obvious
what it is doing. I'd also want to see some more detailed comments in the code
about what it is doing and why.

Maintainability of these kinds of fixes is key.

Cheers,

Richard