Achieve this by adding a MAIN_FUNCTION macro, consolidating the docs, and
introducing the macro across our distributed binaries.
Also update the docs to explain that anyone using binutils < 2.36 is
effected by this issue. Release builds are not, because they use binutils
2.37. Currently LTS Linux distros, like Ubuntu Focal, ship with 2.34.
https://packages.ubuntu.com/focal/binutils
Assigning TIME_INIT to nTime was needed to fully re-initialize a dirty
object where the deserialization might skip nTime.
See https://github.com/bitcoin/bitcoin/pull/19020/files#r427620111
Now that the without-nTime logic is removed in commit
dbcb5742c4 and commit
e08770bed1, the logic here can be removed
as well.
Also, remove confusing and redundant preprocessor code.
Also, remove no longer needed version.h include, which was needed for
INIT_PROTO_VERSION.
This header was included since the introduction of bitcoin-util in
commit 13762bcc96, but boost was
actually never used (see `git log -S boost ./src/bitcoin-util.cpp`).
Consolidate to outputting the licensing info when we pass -version to a binary,
i.e bitcoind -version:
```bash
itcoin Core version v22.99.0-fc1f355913f6-dirty
Copyright (C) 2009-2022 The Bitcoin Core developers
Please contribute if you find Bitcoin Core useful. Visit
<https://bitcoincore.org/> for further information about the software.
The source code is available from <https://github.com/bitcoin/bitcoin>.
This is experimental software.
Distributed under the MIT software license, see the accompanying file COPYING
or <https://opensource.org/licenses/MIT>
```
54ce4fac80 build: improve macro for testing -latomic requirement (fanquake)
2c010b9c56 add std::atomic include to bitcoin-util.cpp (fanquake)
Pull request description:
Since the merge of #19937, riscv builds have been failing, due to a link issue with [`std::atomic_exchange`](https://en.cppreference.com/w/cpp/atomic/atomic_exchange) in `bitcoin-util`:
```bash
CXXLD bitcoin-util
bitcoin_util-bitcoin-util.o: In function `grind_task':
/home/ubuntu/build/bitcoin/distsrc-riscv64-linux-gnu/src/bitcoin-util.cpp:98: undefined reference to `__atomic_exchange_1'
collect2: error: ld returned 1 exit status
```
We have a [macro](https://github.com/bitcoin/bitcoin/blob/master/build-aux/m4/l_atomic.m4) that tries to determine when `-latomic` is required, however it doesn't quite work well enough, as it's currently determining it isn't needed:
```bash
./autogen.sh
./configure --prefix=/home/ubuntu/bitcoin/depends/riscv64-linux-gnu
...
checking whether std::atomic can be used without link library... yes
```
This PR adds a call to `std::atomic_exchange` to the macro, which will get us properly linked against `-latomic` on riscv:
```bash
checking whether std::atomic can be used without link library... no
checking whether std::atomic needs -latomic... yes
```
Also adds an `<atomic>` include to `bitcoin-util.cpp`.
ACKs for top commit:
laanwj:
Tested ACK 54ce4fac80
Tree-SHA512: 963c875097ee96b131163ae8109bcf8fecf4451d20faa2f3d223f9938ea3d8d1ed5604e12ad82c2b4b1c605fd293a9b6b08fefc00dd3e68d09c49e95029c6f50
The binutils we use for gitian builds strips the reloc section from
Windows binaries, which breaks ASLR. As a temporary workaround, export
main(). This is the same workaround as #18702 (bitcoin-cli), and will
fix the currently failing security check:
```bash
+ make -j1 -C src check-security
make: Entering directory '/home/ubuntu/build/bitcoin/distsrc-x86_64-w64-mingw32/src'
Checking binary security...
bitcoin-util.exe: failed RELOC_SECTION
make: *** [check-security] Error 1
```
Relevant upstream issue:
https://sourceware.org/bugzilla/show_bug.cgi?id=19011
