std::uniform_real_distribution allows initializing with non-floating-point types

[ngzhian]

Probably missing a static assert somewhere:
https://github.com/llvm/llvm-project/blob/main/libcxx/include/__random/uniform_real_distribution.h#L28

Like in https://github.com/gcc-mirror/gcc/blob/master/libstdc%2B%2B-v3/include/bits/random.h#L1781

[philnik777]

Where exactly does the standard forbid instantiating uniform_real_distribution with a non-floating-point type?

[ngzhian]

You're right, it doesn't forbid, though it is undefined behavior, so maybe ubsan can warn about it? https://en.cppreference.com/w/cpp/numeric/random/uniform_real_distribution "The result type generated by the generator. The effect is undefined if this is not one of float, double, or long double."

[philnik777]

Maybe more general: http://eel.is/c++draft/rand.req.genl should be enforced by adding correspinding static_asserts.

[llvmbot]

Hi!

This issue may be a good introductory issue for people new to working on LLVM. If you would like to work on this issue, your first steps are:

1. Assign the issue to you.
2. Fix the issue locally.
3. Run the test suite locally.
   3.1) Remember that the subdirectories under test/ create fine-grained testing targets, so you can
   e.g. use make check-clang-ast to only run Clang's AST tests.
4. Create a git commit
5. Run git clang-format HEAD~1 to format your changes.
6. Submit the patch to Phabricator.
   6.1) Detailed instructions can be found here

For more instructions on how to submit a patch to LLVM, see our documentation.

If you have any further questions about this issue, don't hesitate to ask via a comment on this Github issue.

@llvm/issue-subscribers-good-first-issue

[SpinSpinSugar]

Hi, I'd like to take this issue on

[changkhothuychung]

Hi I would like to work on this if this can be assigned to me.

[changkhothuychung]

@philnik777 phil
I can't create a new patch on Phabricator. It says New revision creation is disabled. Please use GitHub Pull Requests instead. Is the process now entirely on Github ?

[EugeneZelenko]

@NhatNguyen1810: Yes, you need to create pull request on GitHub.