Author: Fahad Nayyar Date: 2023-01-13T16:04:42Z New Revision: 4c37671a7c946ac246b52fa44a6a649b89d6310b
URL: https://github.com/llvm/llvm-project/commit/4c37671a7c946ac246b52fa44a6a649b89d6310b DIFF: https://github.com/llvm/llvm-project/commit/4c37671a7c946ac246b52fa44a6a649b89d6310b.diff LOG: [Clang][Sema] Enabled implicit conversion warning for CompoundAssignment operator. This change enables implicit conversion warnings (like Wshorten-64-to-32) for compound assignment operator with integral operands. rdar://10466193 Differential Revision: https://reviews.llvm.org/D139114 Added: Modified: clang/docs/ReleaseNotes.rst clang/lib/Sema/SemaChecking.cpp clang/test/Sema/conversion-64-32.c Removed: ################################################################################ diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index 92de83bae01cd..e8b61db26a860 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -351,6 +351,9 @@ Bug Fixes Improvements to Clang's diagnostics ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ +- Clang now supports implicit conversion warnings (``-Wsign-conversion``, + ``Wshorten-64-to-32``, etc) for compound assignment operators (like +=, -=, <<=, >>= etc) + with integral operands. - Clang will now check compile-time determinable string literals as format strings. Fixes `Issue 55805: <https://github.com/llvm/llvm-project/issues/55805>`_. - ``-Wformat`` now recognizes ``%b`` for the ``printf``/``scanf`` family of diff --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp index 1d956fadcf670..b3834c830d7b7 100644 --- a/clang/lib/Sema/SemaChecking.cpp +++ b/clang/lib/Sema/SemaChecking.cpp @@ -13508,8 +13508,13 @@ static void DiagnoseFloatingImpCast(Sema &S, Expr *E, QualType T, } } +static void CheckImplicitConversion(Sema &S, Expr *E, QualType T, + SourceLocation CC, + bool *ICContext = nullptr, + bool IsListInit = false); + /// Analyze the given compound assignment for the possible losing of -/// floating-point precision. +/// floating-point precision and for implicit conversions for integral operands. static void AnalyzeCompoundAssignment(Sema &S, BinaryOperator *E) { assert(isa<CompoundAssignOperator>(E) && "Must be compound assignment operation"); @@ -13526,8 +13531,17 @@ static void AnalyzeCompoundAssignment(Sema &S, BinaryOperator *E) { ->getComputationResultType() ->getAs<BuiltinType>(); + // Check for implicit conversions for compound assignment statements with + // intergral operands. + // FIXME: should this handle floating-point as well? + if (E->getLHS()->getType()->isIntegerType() && + E->getRHS()->getType()->isIntegerType() && !E->isShiftAssignOp()) + CheckImplicitConversion(S, E->getRHS(), E->getType(), + E->getRHS()->getExprLoc()); + // The below checks assume source is floating point. - if (!ResultBT || !RBT || !RBT->isFloatingPoint()) return; + if (!ResultBT || !RBT || !RBT->isFloatingPoint()) + return; // If source is floating point but target is an integer. if (ResultBT->isInteger()) @@ -13816,9 +13830,8 @@ static void DiagnoseIntInBoolContext(Sema &S, Expr *E) { } static void CheckImplicitConversion(Sema &S, Expr *E, QualType T, - SourceLocation CC, - bool *ICContext = nullptr, - bool IsListInit = false) { + SourceLocation CC, bool *ICContext, + bool IsListInit) { if (E->isTypeDependent() || E->isValueDependent()) return; const Type *Source = S.Context.getCanonicalType(E->getType()).getTypePtr(); diff --git a/clang/test/Sema/conversion-64-32.c b/clang/test/Sema/conversion-64-32.c index 3de20cb0fda3a..6b9d2e2ff35ae 100644 --- a/clang/test/Sema/conversion-64-32.c +++ b/clang/test/Sema/conversion-64-32.c @@ -17,3 +17,36 @@ int4 test1(long2 a) { int test2(long v) { return v / 2; // expected-warning {{implicit conversion loses integer precision: 'long' to 'int'}} } + +// rdar://10466193 +void test3(int i, long long ll) { + i += ll; // expected-warning {{implicit conversion loses integer precision}} + i -= ll; // expected-warning {{implicit conversion loses integer precision}} + i *= ll; // expected-warning {{implicit conversion loses integer precision}} + i /= ll; // expected-warning {{implicit conversion loses integer precision}} +} + +void test4(int i, long long ll) { + i += i-ll; // expected-warning {{implicit conversion loses integer precision}} + i += i+ll; // expected-warning {{implicit conversion loses integer precision}} + i -= i-ll; // expected-warning {{implicit conversion loses integer precision}} + i -= i+ll; // expected-warning {{implicit conversion loses integer precision}} +} + +void test5(int i, int j, long long ll) { + i += (i-j)*ll; // expected-warning {{implicit conversion loses integer precision}} + i += (i+j)*ll; // expected-warning {{implicit conversion loses integer precision}} + i -= ll/(i-j); // expected-warning {{implicit conversion loses integer precision}} + i -= ll/(i-j); // expected-warning {{implicit conversion loses integer precision}} +} + +void test6(char c) { + c <<= 999999; // expected-warning {{shift count >= width of type}} \ + // cxx17-warning {{shift count >= width of type}} \ + // ref-warning {{shift count >= width of type}} \ + // ref-cxx17-warning {{shift count >= width of type}} + c >>= 999999; // expected-warning {{shift count >= width of type}} \ + // cxx17-warning {{shift count >= width of type}} \ + // ref-warning {{shift count >= width of type}} \ + // ref-cxx17-warning {{shift count >= width of type}} +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
