Chromium Ninja build fails (Illegal Instruction output) - chromium

I followed the Linux build instructions and when I try running "ninja -C out/Debug chrome", I just get the output "Illegal Instruction (core dumped)". Now, I wish I could actually find where the core dump is located to see if there is more specific information in there...
For reference, I am trying to run Ninja on Ubuntu 13.10.
Has anyone else experienced this while building Chromium or while trying to build anything else using Ninja? Also, where could I find the core dump?

The error message "Illegal Instruction (core dumped)" indicates that the current binary is using an instruction that is not supported by your CPU.
Please check whether software used for compilation (compiler, linker, ar, ninja-build etc.) is matching your CPU architecture. Unless you have no fancy system like ARM or POWER, you mixed up 32 bit (e.g. i586) and 64 bit (x86-64).
Or you compile to a wrong target. Does your compiler flags include flags beginning with -m like "-march="? That could lead to the same error but only if the compiled code is executed.
Have you built gyp or ninja-build yourself? This would be an other place to make such a mistake.

Related

qt5 build with cmake on window: ERROR: C++11 <random> is required and is missing or failed to compile

My env:
Qt source: dev branch
cmake version: 3.18.4.0
os: windows
Build step:
cd qt_source
mkdir build
cd build
cmake -DMAKE_BUILD_TYPE=Release ..
Then error raised:
ERROR: C++11 <random> is required and is missing or failed to compile.
ERROR: detected a std::atomic implementation that fails for function pointers. Please apply the patch corresponding to your Standard Library vendor, found in qtbase/config.tests/atomicfptr
How can I debug this?
Update on 2020/10/26:
I used the vcpkg install qt5 and it works.
I'd recommend you to use a bit more stable Qt branch, e.g. 5.15.1 or 5.12, otherwise you should be aware that dev branch is on-going development of new features and Qt 6 (as of 01/11/2019), and all bug fixes that are not only relevant for Qt 5 (as of 15/05/2020).
From my practical experience, current dev branch always need some tricks to use and brings lots of problems. If you still need to test some feature that is available only in dev -- consider switch to some stable branch and cherry-pick changes you are interested in.
I was getting this error when trying to build Qt itself from sources with Visual Studio 16 2019 generator. Turned out, it is not supported (yet?), so I had to use Ninja generator instead (and set C/C++ compiler to cl.exe) - then the configuration and build went fine.
So perhaps that is the case with building projects too - you should check if you are using Ninja (and switch to it if not).

How to run a dynamically linked executable syscall emulation mode se.py in gem5?

After How to solve "FATAL: kernel too old" when running gem5 in syscall emulation SE mode? I managed to run a statically linked hello world under certain conditions.
But if I try to run an ARM dynamically linked one against the stdlib with:
./out/common/gem5/build/ARM/gem5.opt ./gem5/gem5/configs/example/se.py -c ./a.out
it fails with:
fatal: Unable to open dynamic executable's interpreter.
How to make it find the interpreter? Hopefully without copying my cross' toolchain's interpreter on my host's root.
For x86_64 it works if I use my native compiler, and as expected strace says that it is using the native interpreter, but it does not work if I use a cross compiler.
The current FAQ says it is not possible to use dynamic executables: http://gem5.org/Frequently_Asked_Questions but I don't trust it, and then these presentations mention it:
http://www.gem5.org/wiki/images/0/0c/2015_ws_08_dynamic-linker.pdf
http://research.cs.wisc.edu/multifacet/papers/learning_gem5_tutorial.pdf
but not how to actually use it.
QEMU user mode has the -L option for that.
Tested in gem5 49f96e7b77925837aa5bc84d4c3453ab5f07408e
https://www.mail-archive.com/gem5-users#gem5.org/msg15582.html
Support for dynamic linking has been added in November 2019
At: https://gem5-review.googlesource.com/c/public/gem5/+/23066
It was working for sure at that point, but then it broke at some point and needs fixing.....
arm 32-bit https://gem5.atlassian.net/browse/GEM5-461
arm 64-bit https://gem5.atlassian.net/browse/GEM5-828
If you have a root filesystem to use, for example one generated by Buildroot you can do:
./build/ARM/gem5.opt configs/example/se.py \
--redirects /lib=/path/to/build/target/lib \
--redirects /lib64=/path/to/build/target/lib64 \
--redirects /usr/lib=/path/to/build/target/usr/lib \
--redirects /usr/lib64=/path/to/build/target/usr/lib64 \
--interp-dir /path/to/build/target \
--cmd /path/to/build/target/bin/hello
Or if you are using an Ubuntu cross compiler toolchain for example in Ubuntu 18.04:
sudo apt install gcc-aarch64-linux-gnu
aarch64-linux-gnu-gcc -o hello.out hello.c
./build/ARM/gem5.opt configs/example/se.py \
--interp-dir /usr/aarch64-linux-gnu \
--redirects /lib=/usr/aarch64-linux-gnu/lib \
--cmd hello.out
You have to add any paths that might contain dynamic libraries as a separate --redirect as well. Those are enough for C executables.
--interp-dir sets the root directory where the dynamic loader will be searched for, based on ELF metadata which says the path of the loader. For example, buildroot ELF files set that path to /lib/ld-linux-aarch64.so.1, and the loader is a file present at /path/to/build/target/lib/ld-linux-aarch64.so.1. As mentioned by Brandon, this path can be found with:
readelf -a $bin_name | grep interp
The main difficulty with syscall emulation dynamic linking, is that we want somehow:
linker file accesses to go to a magic directory to find libraries there
other file accesses from the main application to go to normal paths, e.g. to read an input file in the current working directory
and it is hard to detect if we are in the loader or not, especially because this can happen via dlopen in the middle of a program.
The --redirects option is a simple solution for that.
For example /lib=/path/to/build/target/lib makes it so that if the guest would access the C standard library /lib/libc.so.6, then gem5 sees that this is inside /lib and redirects the path to /path/to/build/target/lib/libc.so.6 instead.
The slight downside is that it becomes impossible to actually access files in the /lib directory of the host, but this is not common, so it works in most cases.
If you miss any --redirect, the dynamic linker will likely complain that the library was not found with a message of type:
hello.out: error while loading shared libraries: libstdc++.so.6: cannot open shared object file: No such file or directory
If that happens, you have to find the libstdc++.so.6 library in the target filesystem / toolchain and add the missing --redirect.
It later broke at https://gem5.atlassian.net/browse/GEM5-430 but was fixed again.
Downsides of dynamic linking
Once I got dynamic linking to work, I noticed that it actually has the following downsides, which might or not be considerable depending on the application:
the dynamic linker has to run some instructions, and if you have a very minimal userland test executable, and are running on a low CPU like O3, then this startup can dominate runtime, so watch out for that
ExecAll does not show symbol names for stdlib functions, you just get offsets from some random nearest symbol e.g. #__end__+274873692728. Maybe something along these lines would work: Debugging shared libraries with gdbserver but not sure
dynamically jumping to a stdlib function for the first time requires going through the dynamic linking machinery, which can create problems if you are trying to control a microbench.
I actually already hit this once: the dynamic version of a program was doing something extra that and that compounded with a gem5 bug broke my experiment, and cost me a few hours of debugging.
Interpreters like Python and Java
Python and Java are just executables, and the script to execute an argument to the executable.
So in theory, you can run them in syscall emulation mode e.g. with:
build/ARM/gem5.opt configs/example/se.py --cmd /usr/bin/python --options='hello.py arg1 arg2'
In practice however hugely complex executable like interpreters are likely to have syscalls that not yet implemented given the current state of gem5 as of November 2019, see also: When to use full system FS vs syscall emulation SE with userland programs in gem5?
Generally it is not hard to implement / ignore uneeded calls though, so give it a shot. Related threads:
Java: Running Java programs in gem5(or any language which is not C)
Python: 3.6.8 aarch64 fails with "fatal: syscall unused#278 (#278) unimplemented.", test setup
Old answer
I have been told that as of 49f96e7b77925837aa5bc84d4c3453ab5f07408e (May 2018) there is no convenient / well tested way for running dynamically linked cross arch executables in syscall emulation: https://www.mail-archive.com/gem5-users#gem5.org/msg15585.html
I suspect however that it wouldn't be very hard to patch gem5 to support it. QEMU user mode already supports that, you just have to point to the root filesystem with -L.
The cross-compiled binary should have an .interp entry if it's a dynamic executable.
Verify it with readelf:
readelf -a $bin_name | grep interp
The simulator is setup to find this section in main executable when it loads the executable into the simulated address space. If this sections exists, a c-string is set to point to that text (normally something like /lib64/ld-linux-x86-64.so.2). The simulator then calls glibc's open function with that c-string as the parameter. Effectively, this opens the dynamic linker-loader for the simulator as a normal file. The simulator then maps the file into the simulated address space in phases with mmap and mmap_fixed.
For cross compilation, this code must fail. The error message follows it directly if the simulator cannot open the file. To make this work, you need to debug the opening process and possibly the subsequent pasting of the loader into the address space. There is mechanism to set the program's entry point into the loader rather than directly into the code section of the main binary. (It's done through the auxiliary vector on the stack.) You may need to play around with that as well.
The interesting code is (as of 05/29/19) in src/base/loader/elf_object.cc.
I encountered this problem after I just cross compiled the code. You can try to add "--static" after the command.

Error in OpenCL kernel compilation

I've included an OpenCL kernel (.cl file) in my OS X framework, and I'm able to reference it from one of my implementation (.m) files.
However, when I compile, I get the following error, related with the kernel:
openclc: error: cannot specify -o when generating multiple output files
This error appears once for every architecture found in the OPENCL_ARCHS build option. I've tried to leave all but one architecture (gpu_64 or gpu_32, tried both), however the error persists.
I went through two examples offered by Apple (Hello World and n-Body simulation, both of which compile and run fine on my system), looking for any special build options, but I failed to find any.
Any thoughts?
Thanks.
EDIT: Added Xcode7 tag, as I am working in Xcode 7 Beta.

How to build zeromq with MinGW?

I've tried official howto but failed. I got error:
"The procedure entry point InterlockedCompareExchange#12 could not be located in the dynamic link library libstdc++-6.dll"
The problem was due the old gcc compiler, bundled with DevKit from rubyinstaller.org (4.5 vs 4.8 on my PC). Use MSYS instead. Assume we have zeromq source inside D:\libs\zeromq, then the procedure is:
Download GUI MinGW installer.
Install base and MSYS (if you already have working gcc compiler you probably only need MSYS).
Launch MSYS environment by executing C:\MinGW\msys\1.0\msys.bat.
Follow Using MSYS with MinGW section:
mount c:/mingw /mingw
cd /d/libs/zeromq
./configure --prefix=/mingw
make
Copy /d/libs/zeromq/src/.libs/libzmq.dll to your desired place.
In fact I needed to use ZeroMQ with C++, so I downloaded zmq.hpp, moved it to include directory, and compiled hwserver.cpp to test it:
C:\MinGW\bin\g++.exe -o hwserver hwserver.cpp -L. -lzmq -ID:\libs\zeromq\include
It worked, but when I launch it I got:
Assertion failed!
Program: D:\tmp\zmq\hwserver.exe
File: D:\libs\zeromq\include/zmq.hpp, Line 280
Expression: rc == 0
This application has requested the Runtime to terminate it in an unusual way.
Please contact the application's support team for more information.
I've managed to get rid of this failure by commenting lines 279, 280. Similar issue

How to cross compile CMake for ARM with CMake

In short I'm trying to cross compile CMake with CMake, and I don't think I'm linking libraries correctly. What I want to do may not be possible, but I'd at least like to know why it isn't possible if that's the case.
System: The host is a Linux box with a Cavium ARM9 CPU. It's currently running version 2.6.24.4 of the Linux kernel and Debian 5.0 (Lenny). My workstation is a Core i5 running Ubuntu 12.04 LTS (Precise Pangolin).
My overall goal is to get ROS running on the Linux box. I have to compile from source rather than use apt since Debian 6.0 (Squeeze) binaries require thumb support that the Cavium does not give, and not many of the needed packages are available for Debian 5.0 (Lenny). I'd made progress installing the various libraries needed, but when I got to step 1.3.1 and tried to run CMake, I got the error
CMake 2.8 or higher is required. You are running version 2.6.0
Next I tried to download and build CMake 2.8.8 on the Linux box itself, but it was too much for the system. When that failed, I downloaded the toolchain suggested on the manufacturer's website and used the cross-compiling guide at [www.cmake.org/Wiki/CMake_Cross_Compiling] to build the CMake executables. Here is my toolchain file:
# This one is important
SET(CMAKE_SYSTEM_NAME Linux)
# Specify the cross compiler
SET(CMAKE_C_COMPILER /pathto/crosstool-linux-gcc-4.5.2-gclibc-2.9-oabi/arm-unknown-linux-gnu/bin/arm-unknown-linux-gnu-gcc)
SET(CMAKE_CXX_COMPILER /pathto/crosstool-linux-gcc-4.5.2-gclibc-2.9-oabi/arm-unknown-linux-gnu/bin/arm-unknown-linux-gnu-g++)
# Where is the target environment
SET(CMAKE_FIND_ROOT_PATH /pathto/crosstool-linux-gcc-4.5.2-gclibc-2.9-oabi/arm-unknown-linux-gnu /pathto/crosstool-linux-gcc-4.5.2-gclibc-2.9-oabi/arm-unknown-linux-gnu/arm-unknown-linux-gnu)
# Search for programs in the build host directories
SET(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
# For libraries and headers in the target directories
SET(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
SET(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)
However, use of the binary on the Linux box gives the error
cmake: /usr/lib/libstdc++.so.6: version `GLIBCXX_3.4.14' not found (required by cmake)
Sure enough, the library is not there:
prompt# strings /usr/lib/libstdc++.so.6 | grep GLIBC
GLIBCXX_3.4
GLIBCXX_3.4.1
GLIBCXX_3.4.2
GLIBCXX_3.4.3
GLIBCXX_3.4.4
GLIBCXX_3.4.5
GLIBCXX_3.4.6
GLIBCXX_3.4.7
GLIBCXX_3.4.8
GLIBCXX_3.4.9
GLIBCXX_3.4.10
GLIBC_2.3
GLIBC_2.0
GLIBC_2.3.2
GLIBC_2.1
GLIBC_2.1.3
GLIBC_2.2
GLIBCXX_FORCE_NEW
GLIBCXX_DEBUG_MESSAGE_LENGTH
I've never cross-compiled before, but I can see one of two scenarios happening: either the binary got created with a link to a higher version of glibcxx on the host machine or the manufacturer's toolchain is more modern than their image. I don't know how to check which is happening or if something else is happening that I don't know about.
My last effort involved trying to statically cross-compile CMake to hopefully get rid of the linking error with
cmake -DCMAKE_TOOLCHAIN_FILE=../toolchain-technologic.cmake -DBUILD_SHARED_LIBS=OFF -DCMAKE_BUILD_TYPE=Release -DCMAKE_EXE_LINKER_FLAGS_RELEASE="-static" ..
I got build errors, and that binary didn't work either. I got:
FATAL: kernel too old
Segmentation fault
I'd try installing glibcxx 3.4.14 on the Linux box, but it doesn't look like it's available for this processor.
I've tried searching for CMake dependencies or system requirements and can't find anything. I've also searched on how to build CMake, but most searches turn up how to build other things with CMake rather than building CMake itself.
I do cross-compile a lot for ARM9 devices using CMake, and indeed this looks like you're not linking to the same libs you have on your target device. You shouldn't need to build CMake yourself to get this done, since it does have good support for cross-compiling since version 2.6. Just make sure you set the CMAKE_FIND_ROOT_PATH variable to a path where you have an exact copy of the root filesystem you have on your target device (with libraries and binaries pre-compiled for the target processor). That should solve your problems.
As a sidenote, I like to use crosstool-ng for building my cross-compilers. It is a really nice tool which helps you to build them from scratch, so I try to match the compiler version and glibc to the ones originally used to build the root filesystem (I usually start with a ready made root filesystem from ARMedslack, since I use Slackware for my development box and ARMedslack for my ARM targets).