Index: clang/lib/StaticAnalyzer/Checkers/PaddingChecker.cpp =================================================================== --- clang/lib/StaticAnalyzer/Checkers/PaddingChecker.cpp +++ clang/lib/StaticAnalyzer/Checkers/PaddingChecker.cpp @@ -193,6 +193,11 @@ CharUnits PaddingSum; CharUnits Offset = ASTContext.toCharUnitsFromBits(RL.getFieldOffset(0)); for (const FieldDecl *FD : RD->fields()) { + // Skip field that is a subobject of zero size, marked with + // [[no_unique_address]] or an empty bitfield, because its address can be + // set the same as the other fields addresses. + if (FD->isZeroSize(ASTContext)) + continue; // This checker only cares about the padded size of the // field, and not the data size. If the field is a record // with tail padding, then we won't put that number in our @@ -249,7 +254,7 @@ RetVal.Field = FD; auto &Ctx = FD->getASTContext(); auto Info = Ctx.getTypeInfoInChars(FD->getType()); - RetVal.Size = Info.Width; + RetVal.Size = FD->isZeroSize(Ctx) ? CharUnits::Zero() : Info.Width; RetVal.Align = Info.Align; assert(llvm::isPowerOf2_64(RetVal.Align.getQuantity())); if (auto Max = FD->getMaxAlignment()) Index: clang/test/Analysis/padding_cpp.cpp =================================================================== --- clang/test/Analysis/padding_cpp.cpp +++ clang/test/Analysis/padding_cpp.cpp @@ -200,3 +200,17 @@ // expected-warning@+1{{Excessive padding in 'class (lambda}} auto lambda1 = [ c1 = G.c1, i = G.i, c2 = G.c2 ]{}; auto lambda2 = [ i = G.i, c1 = G.c1, c2 = G.c2 ]{}; // no-warning + +// expected-warning@+1{{Excessive padding in 'struct NoUniqueAddressWarn' (6 padding}} +struct NoUniqueAddressWarn { + char c1; + [[no_unique_address]] Empty empty; + int i; + char c2; +}; + +struct NoUniqueAddressNoWarn { // no-warning + char c1; + [[no_unique_address]] Empty empty; + char c2; +};