On 10/12/20 18:39 +0100, Vladimir V via Libstdc++ wrote:
Hello.
Could you please have a look at my trivial patch.
It works as intended with avr-libc and doesn't seem to introduce
regressions for x86_64 hosts.
I've pushed this to master now, thanks for the patch.
What would be your suggestions for testing?
Thank you
Vladimir
чт, 10 дек. 2020 г. в 00:00, Vladimir V <vv.os....@gmail.com>:
Thank you for the quick response.
The patch solves the problem.
ср, 9 дек. 2020 г. в 18:01, Jonathan Wakely <jwak...@redhat.com>:
On 09/12/20 12:49 +0000, Jonathan Wakely wrote:
>On 09/12/20 13:32 +0100, Vladimir V wrote:
>>Hello.
>>
>>While testing with the current upstream I encountered a compilation
issue.
>>Although I build with "--disable-threads" flag the following error
occurs:
>>
>>../../../../../libstdc++-v3/src/c++11/thread.cc:39:4: error: #error "No
>>sleep function known for this target"
>>
>>Previously the check was inside the #ifdef _GLIBCXX_HAS_GTHREADS that
>>prevented the error from happening (in my case with gcc v10.1),
>>So I would like to ask if the thread.cc should be involved in the build
if
>>the threads support is configured to be disabled?
>
>Yes, the file is always built, but which definitions it contains
>depends on what is configured for the target.
>
>The std::this_thread::sleep_for and std::this_thread::sleep_until
>functions don't actually depend on threads at all. They just sleep.
>
>But that still requires target support, just different support from
>threads.
>
>>And if it should, then can the condition be reworked to cover the
described
>>case?
>
>Yes, I'll do that. Thanks for bringing it to my attention.
>
>I assume we can't use avr-libc's delay functions, because they depend
>on the CPU clock frequency, which isn't known when we compile
>libstdc++. So I'll just suppress the declarations of those functions
>and remove the #error.
The attached patch adds a new _GLIBCXX_NO_SLEEP configure macro which
should get defined for your hosted AVR build. That should mean that
std::this_thread::sleep_for is not defined, and src/c++11/thread.cc
will no longer insist on some way to sleep being supported.
I've only tested this on powerpc64le-linux, so please let me know if
it works for you.
Pushed to master.
From fbb2144b56625adf594f8812189b983fa66c910a Mon Sep 17 00:00:00 2001
From: Vladimir Vishnevsky <vv.os....@gmail.com>
Date: Tue, 8 Dec 2020 21:45:26 +0100
Subject: [PATCH] Disabling AC_LIBTOOL_DLOPEN check if building with avr-libc
The AC_LIBTOOL_DLOPEN checks were previously disabled for newlib targets.
The patch applies similar logic to avr-libc based builds.
2020-12-08 Vladimir Vishnevsky <vv.os....@gmail.com>
libstdc++-v3/ChangeLog:
Disabling AC_LIBTOOL_DLOPEN check if building with avr-libc.
* configure.ac: Skip AC_LIBTOOL_DLOPEN check if avr-libc is used.
* configure: Regenerate.
---
libstdc++-v3/configure.ac | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/libstdc++-v3/configure.ac b/libstdc++-v3/configure.ac
index cbfdf4c6bad..771814110a1 100644
--- a/libstdc++-v3/configure.ac
+++ b/libstdc++-v3/configure.ac
@@ -90,7 +90,7 @@ AC_SYS_LARGEFILE
GLIBCXX_CONFIGURE
# Libtool setup.
-if test "x${with_newlib}" != "xyes"; then
+if test "x${with_newlib}" != "xyes" && test "x${with_avrlibc}" != "xyes"; then
AC_LIBTOOL_DLOPEN
fi
AM_PROG_LIBTOOL
--
2.17.1
