Enable clang-tidy's bugprone-reserved-identifier check

[sebproell]

As requested in #15870 (comment)

[peterrum]

clang-tidy 3.5 hours. Is that reasonable!? Normally, it takes about 1h!

[tamiko]

We need to get the tidy test to run within around 60 minutes.

[sebproell]

clang-tidy 3.5 hours.

Interesting. I suppose that's the reason why this and other checks haven't been enabled so far ;)

I don't know of a way to get this faster. Close?

[blaisb]

Ohh I had not spotted that the CI was failing because of a timeout. That is an absurd time...

[tamiko]

@blaisb It was running only for around 3h at that point 😄

[peterrum]

I am wondering why this check is sooo expensive? It seems harmless. I have restarted the test to see if we were just unlucky with the worker.

[tamiko]

@peterrum 3h later. Something is seriously wrong.
@sebproell Let's keep the PR open for a little while for us to figure out what the problem is.

[bangerth]

@sebproell Do you have a way to check on your local machine how long the clang-tidy runs take with/without the new flag?

[peterrum]

@sebproell Do you have a way to check on your local machine how long the clang-tidy runs take with/without the new flag?

@sebproell ?

[sebproell]

@bangerth @peterrum

Sorry. I missed that comment. I can have a look.

[sebproell]

On my machine (20 threads, 64GB RAM) using LLVM 17.2 I get for the run of clang-tidy (without the initial CMake setup and partial build):

With the new check enabled:

real    9m0.901s
user    163m31.015s
sys     3m32.260s

without the new check enabled:

real    8m16.128s
user    151m31.455s
sys     3m23.315s

So, the check is also slower here but not as crazy as in GitHub actions.

[sebproell]

I hacked my local clang-tidy installation to extract the timings for different checks:

Total                                              7582.16
performance-unnecessary-value-param                1437.7
bugprone-reserved-identifier                       773.906
modernize-type-traits                              725.428
modernize-macro-to-enum                            649.872
modernize-use-nullptr                              465.248
performance-unnecessary-copy-initialization        447.684
performance-move-const-arg                         408.061
modernize-deprecated-ios-base-aliases              379.476
modernize-replace-auto-ptr                         356.463
modernize-use-using                                236.725
modernize-use-bool-literals                        231.525
performance-type-promotion-in-math-fn              191.077
modernize-redundant-void-arg                       180.396
modernize-use-noexcept                             138.601
modernize-use-uncaught-exceptions                  118.016
modernize-use-equals-default                       113.685
readability-qualified-auto                         68.666
modernize-loop-convert                             59.8898
performance-no-int-to-ptr                          56.1777
modernize-replace-random-shuffle                   56.1364
modernize-use-equals-delete                        48.3806
modernize-avoid-bind                               47.1116
modernize-use-emplace                              46.3092
mpi-type-mismatch                                  43.0508
performance-noexcept-swap                          40.6276
performance-avoid-endl                             40.3881
mpi-buffer-deref                                   37.5569
performance-inefficient-algorithm                  35.5613
performance-noexcept-move-constructor              31.2544
modernize-make-shared                              22.6631
modernize-deprecated-headers                       20.1787
modernize-make-unique                              17.9784
cppcoreguidelines-pro-type-static-cast-downcast    14.6678
performance-move-constructor-init                  12.6691
misc-definitions-in-headers                        6.9102
performance-faster-string-find                     6.1621
modernize-shrink-to-fit                            5.4204
performance-inefficient-vector-operation           4.3713
modernize-unary-static-assert                      2.2121
performance-trivially-destructible                 2.0579
performance-noexcept-destructor                    1.4932
performance-for-range-copy                         0.2467
performance-implicit-conversion-in-loop            0.1536

[bangerth]

So what do we want to do about this? The CI isn't my forte, so others will have to make the call.

[masterleinad]

So what do we want to do about this? The CI isn't my forte, so others will have to make the call.

I don't think it's worth spending more time on this.

[sebproell]

I don't have an idea right now. Closing.