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[clang][analyzer] Fix InvalidatedIterator crash caused by overload operator member function with explicit this #132581

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Merged
merged 3 commits into from
Mar 24, 2025
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[clang][analyzer] Fix InvalidatedIterator crash caused by overload operator member function with explicit this #132581

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67ebfb0
[clang][analyzer] Fix crash caused by overload operator member functi…
flovent Mar 23, 2025
a418a8a
move releated test to InvalidatedIteratorChecker's original testfile
flovent Mar 24, 2025
347c65d
add missing newline
flovent Mar 24, 2025
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7 changes: 5 additions & 2 deletions clang/lib/StaticAnalyzer/Checkers/ContainerModeling.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -157,8 +157,11 @@ void ContainerModeling::checkPostCall(const CallEvent &Call,
if (Func->isOverloadedOperator()) {
const auto Op = Func->getOverloadedOperator();
if (Op == OO_Equal) {
// Overloaded 'operator=' must be a non-static member function.
const auto *InstCall = cast<CXXInstanceCall>(&Call);
// Only handle the assignment operator with implicit this
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Maybe a FIXME with a GitHub ticket to properly support explicit could be nice.

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Actually, it shouldn't be too hard to fix this. Only like 5 lines of code I imagine.
At that point, it may be easier to fix it instead of creating a ticket.

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I think I may not understand correctly, what should i fix here? explicit this will not appear in STL containers' member function.

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I think it's technically possible to have a conforming STL implementation using "deducing this" in their implementation.
I agree that it's bikshedding. I'd just say let's move on. We don't even need a GH ticket. I think there are far more pressing issues to track other than this tiny marginal edge case.

const auto *InstCall = dyn_cast<CXXInstanceCall>(&Call);
if (!InstCall)
return;

if (cast<CXXMethodDecl>(Func)->isMoveAssignmentOperator()) {
handleAssignment(C, InstCall->getCXXThisVal(), Call.getOriginExpr(),
Call.getArgSVal(0));
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25 changes: 24 additions & 1 deletion clang/test/Analysis/invalidated-iterator.cpp
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@@ -1,5 +1,6 @@
// RUN: %clang_analyze_cc1 -std=c++11 -analyzer-checker=core,cplusplus,alpha.cplusplus.InvalidatedIterator -analyzer-config aggressive-binary-operation-simplification=true -analyzer-config c++-container-inlining=false %s -verify
// RUN: %clang_analyze_cc1 -std=c++11 -analyzer-checker=core,cplusplus,alpha.cplusplus.InvalidatedIterator -analyzer-config aggressive-binary-operation-simplification=true -analyzer-config c++-container-inlining=true -DINLINE=1 %s -verify
// RUN: %clang_analyze_cc1 -std=c++23 -analyzer-checker=core,cplusplus,alpha.cplusplus.InvalidatedIterator -analyzer-config aggressive-binary-operation-simplification=true -analyzer-config c++-container-inlining=true -DINLINE=1 %s -verify

#include "Inputs/system-header-simulator-cxx.h"

Expand Down Expand Up @@ -204,4 +205,26 @@ void invalidated_subscript_end_ptr_iterator(cont_with_ptr_iterator<int> &C) {
auto i = C.begin();
C.erase(i);
(void) i[1]; // expected-warning{{Invalidated iterator accessed}}
}
}

#if __cplusplus >= 202302L
namespace GH116372 {
class ExplicitThis {
int f = 0;
public:
ExplicitThis();
ExplicitThis(ExplicitThis& other);

ExplicitThis& operator=(this ExplicitThis& self, ExplicitThis const& other) { // no crash
self.f = other.f;
return self;
}

~ExplicitThis();
};

void func(ExplicitThis& obj1) {
obj1 = obj1;
}
}
#endif
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