Fix -Wtautological-constant-out-of-range-compare warnings on 32-bit systems #19735

1. 
   hebasto commented at 9:38 am on August 16, 2020: member

   On 32-bit system

   0$ uname -nrmo
   1odroid-hc1 4.14.187-odroidxu4 armv7l GNU/Linux
   2$ lsb_release -ds
   3Ubuntu 20.04.1 LTS
   4$ clang --version
   5clang version 10.0.0-4ubuntu1 
   6Target: armv7l-unknown-linux-gnueabihf
   7Thread model: posix
   8InstalledDir: /usr/bin
   

   the clang fires the following warnings:

    0  CXX      policy/libbitcoin_common_a-feerate.o
    1policy/feerate.cpp:14:20: warning: result of comparison of constant 9223372036854775807 with expression of type 'size_t' (aka 'unsigned int') is always true [-Wtautological-constant-out-of-range-compare]
    2    assert(nBytes_ <= uint64_t(std::numeric_limits<int64_t>::max()));
    3           ~~~~~~~ ^  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    4/usr/include/assert.h:93:27: note: expanded from macro 'assert'
    5     (static_cast <bool> (expr)                                         \
    6                          ^~~~
    7policy/feerate.cpp:25:20: warning: result of comparison of constant 9223372036854775807 with expression of type 'size_t' (aka 'unsigned int') is always true [-Wtautological-constant-out-of-range-compare]
    8    assert(nBytes_ <= uint64_t(std::numeric_limits<int64_t>::max()));
    9           ~~~~~~~ ^  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   10/usr/include/assert.h:93:27: note: expanded from macro 'assert'
   11     (static_cast <bool> (expr)                                         \
   12                          ^~~~
   132 warnings generated.
   

   Fix is safe as https://github.com/bitcoin/bitcoin/blob/a57af897ec16976b28de05aa0b9c3f6a96d73ede/src/compat/assumptions.h#L55-L59

2. DrahtBot added the label TX fees and policy on Aug 16, 2020
3. 
   practicalswift commented at 4:29 pm on August 16, 2020: contributor

   Concept ACK

   Please consider enabling -Wtautological-constant-out-of-range-compare too :)

4. 
   hebasto commented at 4:39 pm on August 16, 2020: member

   Please consider enabling -Wtautological-constant-out-of-range-compare too :)

   Isn’t it enabled by default? https://clang.llvm.org/docs/DiagnosticsReference.html#wtautological-constant-out-of-range-compare

5. 
   theStack commented at 7:59 pm on September 6, 2020: member

   Code Review ACK 7c30e9f6f2f18057366383cb2b0a54d99731041c
6. 
   DrahtBot commented at 6:09 am on November 29, 2020: member

   The following sections might be updated with supplementary metadata relevant to reviewers and maintainers.

   Conflicts

   Reviewers, this pull request conflicts with the following ones:

   • #21848 (refactor: Make CFeeRate constructor architecture-independent by MarcoFalke)

   If you consider this pull request important, please also help to review the conflicting pull requests. Ideally, start with the one that should be merged first.

7. in src/policy/feerate.cpp:23 in 7c30e9f6f2 outdated

   18@@ -20,7 +19,6 @@ CFeeRate::CFeeRate(const CAmount& nFeePaid, size_t nBytes_)
   19 
   20 CAmount CFeeRate::GetFee(size_t nBytes_) const
   21 {
   22-    assert(nBytes_ <= uint64_t(std::numeric_limits<int64_t>::max()));
   

   ---

   ---

   

   MarcoFalke commented at 10:27 am on May 4, 2021:

   How is this assert save to remove for 64-bit?

   ---

   

   hebasto commented at 11:52 am on May 7, 2021:

   Oh, my bad!

   Thanks! Updated.

8. hebasto force-pushed on May 7, 2021
9. 
   hebasto commented at 11:51 am on May 7, 2021: member

   Updated 7c30e9f6f2f18057366383cb2b0a54d99731041c -> 3759a5b3be7a88f265a282388af603b27e458ec0 (pr19735.01 -> pr19735.02):

   • rebased
   • addressed @MarcoFalke’s comment
10. Fix -Wtautological-constant-out-of-range-compare warnings on 32-bit

    It is safe, see assumptions.h:
    "We assume size_t to be 32-bit or 64-bit."

    c092473d92
11. Drop redundant `static_assert`s

    It is safe, see assumptions.h:
    "We assume size_t to be 32-bit or 64-bit."

    65ea9aae3d
12. hebasto force-pushed on May 7, 2021
13. 
    DrahtBot commented at 9:40 am on May 24, 2021: member

    🐙 This pull request conflicts with the target branch and needs rebase.

    Want to unsubscribe from rebase notifications on this pull request? Just convert this pull request to a “draft”.

14. DrahtBot added the label Needs rebase on May 24, 2021
15. 
    hebasto commented at 10:31 am on May 24, 2021: member

    The problem has been resolved in #21848 :tiger2:
16. hebasto closed this on May 24, 2021

    ---

17. hebasto deleted the branch on May 24, 2021
18. fanquake removed the label Needs rebase on May 31, 2021
19. DrahtBot locked this on Aug 18, 2022

Contributors
hebasto practicalswift theStack DrahtBot MarcoFalke

Labels
TX fees and policy