`<numeric>`: error C3198: invalid use of floating-point pragmas: fenv_access pragma operates only in precise mode
Open
Nobody has claimed this yet.
bug
- Dominant language
- C++
- Stars
- 11.1k
- Forks
- 1.7k
- Avg merge
- 4d 15h
- Merged PRs (30d)
- 22
Description
Describe the bug
Enabling fenv_access prior to including <numeric> triggers error C3198.
Command-line test case
// float_control.cpp
#pragma fenv_access(on)
#include <numeric>
int main() {}
D:\>cl /std:c++17 float_control.cpp
Microsoft (R) C/C++ Optimizing Compiler Version 19.31.31104 for x64
Copyright (C) Microsoft Corporation. All rights reserved.
float_control.cpp
C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.31.31103\include\numeric(52): error C3198: invalid use of floating-point pragmas: fenv_access pragma operates only in precise mode
C:\Program Files\Microsoft Visual Studio\2022\Community\VC\Tools\MSVC\14.31.31103\include\numeric(158): error C3198: invalid use of floating-point pragmas: fenv_access pragma operates only in precise mode
Expected behavior
No error.
STL version
Microsoft Visual Studio Community 2022 (64-bit) - Current
Version 17.1.1
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Start with the provided float_control.cpp reproduction and inspect the header locations reported at lines 52 and 158. Run the MSVC command shown with /std:c++17, then trace the floating-point pragma handling in those header sections. Done means enabling fenv_access before including no longer produces C3198.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- cpp
- Domain
- compilers
- Issue type
- Bug
- Difficulty
- 3/5
- Estimated time
- 1-2 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 45/100