Thread Safety Analysis warnings #18636

After removing spammy warnings (#18635), when compiling with -Wthread-safety some warnings are observed:

$ make > /dev/null
blockencodings.cpp:109:28: warning: reading variable 'vTxHashes' requires holding mutex 'cs' [-Wthread-safety-precise]
    for (size_t i = 0; i < vTxHashes.size(); i++) {
                           ^
blockencodings.cpp:109:28: note: found near match 'pool->cs'
blockencodings.cpp:110:50: warning: reading variable 'vTxHashes' requires holding mutex 'cs' [-Wthread-safety-precise]
        uint64_t shortid = cmpctblock.GetShortID(vTxHashes[i].first);
                                                 ^
blockencodings.cpp:110:50: note: found near match 'pool->cs'
blockencodings.cpp:114:47: warning: reading variable 'vTxHashes' requires holding mutex 'cs' [-Wthread-safety-precise]
                txn_available[idit->second] = vTxHashes[i].second->GetSharedTx();
                                              ^
blockencodings.cpp:114:47: note: found near match 'pool->cs'
3 warnings generated.
net_processing.cpp:561:17: warning: reading variable 'lNodesAnnouncingHeaderAndIDs' requires holding mutex 'cs_main' [-Wthread-safety-analysis]
            if (lNodesAnnouncingHeaderAndIDs.size() >= 3) {
                ^
net_processing.cpp:564:34: warning: reading variable 'lNodesAnnouncingHeaderAndIDs' requires holding mutex 'cs_main' [-Wthread-safety-analysis]
                connman->ForNode(lNodesAnnouncingHeaderAndIDs.front(), [connman, nCMPCTBLOCKVersion](CNode* pnodeStop){
                                 ^
net_processing.cpp:569:17: warning: reading variable 'lNodesAnnouncingHeaderAndIDs' requires holding mutex 'cs_main' [-Wthread-safety-analysis]
                lNodesAnnouncingHeaderAndIDs.pop_front();
                ^
net_processing.cpp:572:13: warning: reading variable 'lNodesAnnouncingHeaderAndIDs' requires holding mutex 'cs_main' [-Wthread-safety-analysis]
            lNodesAnnouncingHeaderAndIDs.push_back(pfrom->GetId());
            ^
net_processing.cpp:1231:9: warning: calling function 'ProcessBlockAvailability' requires holding mutex 'cs_main' exclusively [-Wthread-safety-analysis]
        ProcessBlockAvailability(pnode->GetId());
        ^
net_processing.cpp:1232:30: warning: calling function 'State' requires holding mutex 'cs_main' exclusively [-Wthread-safety-analysis]
        CNodeState &state = *State(pnode->GetId());
                             ^
net_processing.cpp:1236:18: warning: calling function 'PeerHasHeader' requires holding mutex 'cs_main' exclusively [-Wthread-safety-analysis]
                !PeerHasHeader(&state, pindex) && PeerHasHeader(&state, pindex->pprev)) {
                 ^
net_processing.cpp:1236:51: warning: calling function 'PeerHasHeader' requires holding mutex 'cs_main' exclusively [-Wthread-safety-analysis]
                !PeerHasHeader(&state, pindex) && PeerHasHeader(&state, pindex->pprev)) {
                                                  ^
net_processing.cpp:3450:33: warning: calling function 'State' requires holding mutex 'cs_main' exclusively [-Wthread-safety-analysis]
            CNodeState *state = State(pnode->GetId());
                                ^
net_processing.cpp:3470:38: warning: calling function 'State' requires holding mutex 'cs_main' exclusively [-Wthread-safety-analysis]
                CNodeState &state = *State(pnode->GetId());
                                     ^
10 warnings generated.

Tested compilers:

$ clang --version
clang version 6.0.0-1ubuntu2 (tags/RELEASE_600/final)
Target: x86_64-pc-linux-gnu
Thread model: posix
InstalledDir: /usr/bin

and

% clang --version
Apple clang version 11.0.3 (clang-1103.0.32.29)
Target: x86_64-apple-darwin19.4.0
Thread model: posix
InstalledDir: /Library/Developer/CommandLineTools/usr/bin

I'm not sure how those cases got merged in the first place. We have at least one Travis job with -Werror=thread-safety-analysis, no? :)

I'm not sure how those cases got merged in the first place. We have at least one Travis job with -Werror=thread-safety-analysis, no? :)

My setup was broken. That is why this issue was closed :)

Nevertheless, mind looking into related #18635 and #18639?

These are just cases where thread-safety-precise is warning about locks being aliased, isn't it?

These are just cases where thread-safety-precise is warning about locks being aliased, isn't it?

Yes, it is. That's why I've closed this issue.

@practicalswift

I'm not sure how those cases got merged in the first place. We have at least one Travis job with -Werror=thread-safety-analysis, no? :)

~No, we haven't any, unfortunately.~ At least "macOS 10.14 native" builds with -Wthread-safety-analysis and -Werror=thread-safety-analysis flags.

UPDATE: Oh, I see your #10866 :)