[diff.expr] Unmentioned incompatibility with C about pointer indirection CWG2875
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Description
These usages of pointer indirection are explicitly allowed in C via WG14 N721, but seemly not allowed in C++.
int* p = &(*((int*)0)); // undefined behavior in C++, well-defined in C (DR076/N721)
int a[10];
int* q = &a[10]; // undefined behavior in C++, well-defined in C (DR076/N721)
Should we mention them in [diff.expr]?
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Research direction
Start by reading the issue examples and WG14 N721, then inspect the [diff.expr] section in the draft. Determine whether the pointer-indirection cases are an omission from the C++ differences documentation; done means the section explicitly addresses the compatibility question or records why it should not.
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Assessment
- Tech stack
- c, cpp
- Domain
- compilers
- Issue type
- Documentation
- Difficulty
- 3/5
- Estimated time
- 1-2 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 35/100