"Timeout" error when adding ppa to install gcc 7.5

I want to install gcc 7.5 and found the following steps on several websites:

sudo apt-get install -y software-properties-common
sudo add-apt-repository ppa:ubuntu-toolchain-r/test
sudo apt update
sudo apt install g++-7 -y

But when I run:

sudo add-apt-repository ppa:ubuntu-toolchain-r/test

Errors are reported:

gpg: keyring /tmp/tmpir2cfkik/secring.gpg' created
gpg: keyring /tmp/tmpir2cfkik/pubring.gpg' created
gpg: requesting key BA9EF27F from hkp server keyserver.ubuntu.com
Error: retrieving gpg key timed out.
gpg: keyserver timed out
gpg: keyserver receive failed: keyserver error

I found someone had the same problem and suggested that it would be useful to run the same command multiple times, but it doesn't work for me.
Does anyone know how to fix this problem?

c ++ – ARM GCC C ++ 14 POD types are not put in the ROM

I experimented with the binary files generated with the ARM GCC compiler (version 9.2.1).
I have found that even if I compiled the program with C ++ 14 support, the mild rules for POD types are not used to insert the structure definition into the Rodata section.

For example:

struct DigitalOut 
   uint32_t port;
   uint32_t pin;
   uin32_t output_type;
   uint32_t output_speed;

This version is inserted into the Rodata section when instantiated with parenthesized initializers.

However, when I introduce the specific constructor for the structure as shown below, it is not inserted in the Rodata section

struct DigitalOut 

   DigitalOut() = default;

   DigitalOut(uint32_t port, uint32_t pin) : 
   output_type{500}  //just an example
   output_speed{400} {}

   uint32_t port;
   uint32_t pin;
   uin32_t output_type;
   uint32_t output_speed;

What am I missing here? I'm pretty sure I understand the updated definition of C ++ for POD types, trivially constructable and copyable classes, and standard layouts.

Link to the response to updated definition POD types

c – Where can I find GCC tools (GCC, assembler and ELF linker) for the PowerPC 440 for use under Linux or Windows?

I need to compile some simple C programs to target the PowerPC 440 architecture. Where can I find the GCC cross compiler tools for PowerPC? I can run on Windows or Linux. You need GCC, the assembler and ELF linker. OR is there another tool set that I should consider that targets the PowerPC 440 core?
Thanks a lot!

Linux – How to build PCRE 8.44 without linking to gcc

I am creating a custom version of Apache HTTPD with a number of additional modules. As part of that, I link to PCRE 8.44, which works well. However, lib/libpcrecpp.so.0.0.2 has a dependency that is displayed for libgcc_s.so.1 via /usr/bin/env -i ldd.

I don't want gcc to be installed on production servers, especially extranet production servers. I can't seem to find a combination of flags that create a PCRE that isn't linked to libgcc. I'm pretty sure disabling C ++ support would do this, but that's hardly optimal and I haven't really tried it.

Is there a way to create PCRE so that it is not linked to gcc?

Current settings are:

LDFLAGS=-Wl,-rpath,${PREFIX}/lib -Wl,-rpath,${PREFIX}/lib64 -L${PREFIX}/lib -L${PREFIX}/lib64
CFLAGS=-Wl,-rpath,${PREFIX}/lib -Wl,-rpath,${PREFIX}/lib64 -I${PREFIX}/include


&& make 
&& make install

(When people have suggestions for better configuration options, I listen.)

macos – When compiling code with gcc on a Mac OS linker, the custom static library could not be linked

Here is the file structure for my project file in C language:
The first is a fullCourse folder
The fullCourse folder contains three folders:
1. Include
2. src
3. lib
4. test
in the include folder:
It contains a header file: temp.h.

The code for temp.h is as follows:

#ifndef __$__temp_h
#define __$__temp_h 234
int yash();

in the src folder:
It contains a source file: temp.c.

The code for temp.cc is as follows:

#ifndef __$__temp_c
#define __$__temp_c 234
int yash()
return 22;

Then stay in the same folder and create the .o file as follows:

gcc -I ../include -c temp.c

The next step was to move this temp.o file to the lib folder as follows:

mv temp.o ../lib

To stay in the lib folder, an archived (or library) file was created as follows:

ar rcs libtmds.a temp.o

as in the test folder wrote a source code in the test library (tempTest.c)
The code for tempTest.c is as follows:

int main()
int w;
return 0;

than staying in the test folder, it tried to compile as follows:

gcc -static -I ../include tempTest.c -L ../lib -ltmds -o tempTest.exe

However, the code has not been compiled and shows the following error:

ld: library not found for -lcrt0.o
clang: error: linker command failed with exit code 1 (use -v to see invocation)

Please help me to solve this problem.

Can memory for swap space be allocated in Linux instead of RAM in C ++ and GCC?

I have a big hash, about 6 gigabytes, that I load into memory. On my current laptop, from which I develop, the number on my system is very high, which leads to massive delays while trying to do other things, e.g. B. debugging or searching a batch overflow. This would not be a problem if I could only store the hash in my swap space while leaving primary storage available for more important programs.

Is it even possible as far as GCC is concerned? Are there memory managers who can do this? If not, what are my best options where I don't need to set up a PostgreSQL server?

I really only need this while I'm debugging. Finally, the program is stored on a server on which this is not necessary.

File system – `apt install gcc` fails because no symlink can be created in / lib

I tried to install GCC using apt, but it barked that it couldn't create a link in /lib,

update-alternatives: error: error creating symbolic 
link '/lib/cpp.dpkg-tmp': Operation not permitted

I started to investigate:

root@Ubuntu-1804-bionic-64-minimal /lib # echo aaa > /lib/delme
-bash: /lib/delme: Operation not permitted
root@Ubuntu-1804-bionic-64-minimal /lib # ls -ld /lib
drwxr-xr-x 17 root root 4096 May 30  2019 /lib
root@Ubuntu-1804-bionic-64-minimal /lib # whoami
root@Ubuntu-1804-bionic-64-minimal /lib # df -h /lib
Filesystem      Size  Used Avail Use% Mounted on
/dev/md2        437G  202G  213G  49% /
root@Ubuntu-1804-bionic-64-minimal /lib # lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description:    Ubuntu 18.04.3 LTS
Release:    18.04
Codename:   bionic
root@Ubuntu-1804-bionic-64-minimal /lib # touch /lib/init/delme

Permissions seem fine, lots of free space, and I can create files in /lib/init but not in /lib, This is an almost standard system, nothing special except that I installed LXD and Node.js. I didn't do anything with the file system, no partitioning, no permissions changed. What could be a problem?

gcc – How to update the version of CXXABI in libstdc ++. so.6

I am currently trying to run a Python program with RDKit and there are errors. I wondered if I should post this on Stack Overflow or here, but some research made me feel that this had something more to do with Ubuntu libstdc++,

The problem is that every time you try to import a Python package, you get the following error message:

ImportError: /usr/lib/x86_64-linux-gnu/libstdc++.so.6: version `CXXABI_1.3.11' not found (required by /home/user1/anaconda3/envs/user1/lib/python3.7/site-packages/rdkit/DataStructs/../../../../libRDKitDataStructs.so.1)

I did a bit of research and managed to do the following:

I have the LD_LIBRARY_PATH Environment variable too /home/user1/anaconda3/lib/ there is mine here libstdc++.so.6 is located. After that, I kept "not being able to find" CXXABI_1.3.11 what is the required version "bug, and so have:

strings /home/user1/anaconda3/lib/libstdc++.so.6 | grep CXXABI

what outputs:


I assume that I need to see something for the original program to run properly CXXABI_1.3.11 if I let that go strings command like me.

Does anyone know how I can update the version here? Thank you very much.

gcc – I am transit in Doha to Mumbai. Can I have multiple Bibles in my check-in bags?

I will travel to Mumbai in a few days. My flight is going to my final destination in Doha. I was worried about traveling with my Bibles.

I know that the GCC countries only allow their visitors a Bible for personal use. Well, I have seven of them for this trip. I will put them in my check-in bags.

I assume that it will be fine since I am visiting and just passing through.

Any thought?