baloghadamsoftware added inline comments.
================
Comment at: lib/StaticAnalyzer/Core/RangeConstraintManager.cpp:511
+ SSE->getLHS()->getType()->isSignedIntegerOrEnumerationType() ||
+ SSE->getLHS()->getType()->isPointerType()) {
+ return negV->Negate(BV, F);
----------------
NoQ wrote:
> Pointer types are currently treated as unsigned, so i'm not sure you want
> them here.
For me it seems that pointer differences are still pointer types and they are
signed. (The range becomes negative upon negative assumption. From test
`ptr-arith.c`:
```
void use_symbols(int *lhs, int *rhs) {
clang_analyzer_eval(lhs < rhs); // expected-warning{{UNKNOWN}}
if (lhs < rhs)
return;
clang_analyzer_eval(lhs < rhs); // expected-warning{{FALSE}}
clang_analyzer_eval(lhs - rhs); // expected-warning{{UNKNOWN}}
if ((lhs - rhs) != 5)
return;
clang_analyzer_eval((lhs - rhs) == 5); // expected-warning{{TRUE}}
}
```
If I put `clang_analyzer_printState()` into the empty line in the middle, I get
the following range for the difference: `[-9223372036854775808, 0]`. If I
replace `int*` with `unsigned`, this range becomes `[0, 0]`, so `int*` is
handled as a signed type here.
https://reviews.llvm.org/D35110
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