[clang] 9bd0db8 - [-Wunsafe-buffer-usage] Bug fix: Handles the assertion violations for code within macros
via cfe-commits
cfe-commits at lists.llvm.org
Mon Apr 24 16:10:23 PDT 2023
Author: MalavikaSamak
Date: 2023-04-24T16:10:15-07:00
New Revision: 9bd0db80784e30d40a4a65f1b47109c833f05b54
URL: https://github.com/llvm/llvm-project/commit/9bd0db80784e30d40a4a65f1b47109c833f05b54
DIFF: https://github.com/llvm/llvm-project/commit/9bd0db80784e30d40a4a65f1b47109c833f05b54.diff
LOG: [-Wunsafe-buffer-usage] Bug fix: Handles the assertion violations for code within macros
When macros get expanded, the source location for the expanded code received by the Fixable
gadgets is invalid. We do not want to emit fixits for macro expanded code and it currently
crashes the analysis. This patch fixes the assertion violations that were introduced for
handling code with such invalid locations.
Reviewed by: NoQ, ziqingluo-90, jkorous
Differential revision: https://reviews.llvm.org/D146450
Added:
Modified:
clang/lib/Analysis/UnsafeBufferUsage.cpp
clang/test/SemaCXX/warn-unsafe-buffer-usage-fixits-local-var-span.cpp
Removed:
################################################################################
diff --git a/clang/lib/Analysis/UnsafeBufferUsage.cpp b/clang/lib/Analysis/UnsafeBufferUsage.cpp
index 7a432ea5323a4..037efc9c5d009 100644
--- a/clang/lib/Analysis/UnsafeBufferUsage.cpp
+++ b/clang/lib/Analysis/UnsafeBufferUsage.cpp
@@ -1117,42 +1117,44 @@ static std::string getAPIntText(APInt Val) {
// Return the source location of the last character of the AST `Node`.
template <typename NodeTy>
-static SourceLocation getEndCharLoc(const NodeTy *Node, const SourceManager &SM,
- const LangOptions &LangOpts) {
+static std::optional<SourceLocation>
+getEndCharLoc(const NodeTy *Node, const SourceManager &SM,
+ const LangOptions &LangOpts) {
unsigned TkLen = Lexer::MeasureTokenLength(Node->getEndLoc(), SM, LangOpts);
SourceLocation Loc = Node->getEndLoc().getLocWithOffset(TkLen - 1);
- // We expect `Loc` to be valid. The location is obtained by moving forward
- // from the beginning of the token 'len(token)-1' characters. The file ID of
- // the locations within a token must be consistent.
- assert(Loc.isValid() && "Expected the source location of the last"
- "character of an AST Node to be always valid");
- return Loc;
+ if (Loc.isValid())
+ return Loc;
+
+ return std::nullopt;
}
// Return the source location just past the last character of the AST `Node`.
template <typename NodeTy>
-static SourceLocation getPastLoc(const NodeTy *Node, const SourceManager &SM,
- const LangOptions &LangOpts) {
+static std::optional<SourceLocation> getPastLoc(const NodeTy *Node,
+ const SourceManager &SM,
+ const LangOptions &LangOpts) {
SourceLocation Loc =
Lexer::getLocForEndOfToken(Node->getEndLoc(), 0, SM, LangOpts);
- // We expect `Loc` to be valid as it is either associated to a file ID or
- // it must be the end of a macro expansion. (see
- // `Lexer::getLocForEndOfToken`)
- assert(Loc.isValid() && "Expected the source location just past the last "
- "character of an AST Node to be always valid");
- return Loc;
+ if (Loc.isValid())
+ return Loc;
+
+ return std::nullopt;
}
// Return text representation of an `Expr`.
-static StringRef getExprText(const Expr *E, const SourceManager &SM,
- const LangOptions &LangOpts) {
- SourceLocation LastCharLoc = getPastLoc(E, SM, LangOpts);
+static std::optional<StringRef> getExprText(const Expr *E,
+ const SourceManager &SM,
+ const LangOptions &LangOpts) {
+ std::optional<SourceLocation> LastCharLoc = getPastLoc(E, SM, LangOpts);
+
+ if (LastCharLoc)
+ return Lexer::getSourceText(
+ CharSourceRange::getCharRange(E->getBeginLoc(), *LastCharLoc), SM,
+ LangOpts);
- return Lexer::getSourceText(
- CharSourceRange::getCharRange(E->getBeginLoc(), LastCharLoc), SM,
- LangOpts);
+ return std::nullopt;
}
std::optional<FixItList>
@@ -1191,12 +1193,24 @@ DerefSimplePtrArithFixableGadget::getFixits(const Strategy &s) const {
CharSourceRange StarWithTrailWhitespace =
clang::CharSourceRange::getCharRange(DerefOp->getOperatorLoc(),
LHS->getBeginLoc());
+
+ std::optional<SourceLocation> LHSLocation = getPastLoc(LHS, SM, LangOpts);
+ if (!LHSLocation)
+ return std::nullopt;
+
CharSourceRange PlusWithSurroundingWhitespace =
- clang::CharSourceRange::getCharRange(getPastLoc(LHS, SM, LangOpts),
- RHS->getBeginLoc());
+ clang::CharSourceRange::getCharRange(*LHSLocation, RHS->getBeginLoc());
+
+ std::optional<SourceLocation> AddOpLocation =
+ getPastLoc(AddOp, SM, LangOpts);
+ std::optional<SourceLocation> DerefOpLocation =
+ getPastLoc(DerefOp, SM, LangOpts);
+
+ if (!AddOpLocation || !DerefOpLocation)
+ return std::nullopt;
+
CharSourceRange ClosingParenWithPrecWhitespace =
- clang::CharSourceRange::getCharRange(getPastLoc(AddOp, SM, LangOpts),
- getPastLoc(DerefOp, SM, LangOpts));
+ clang::CharSourceRange::getCharRange(*AddOpLocation, *DerefOpLocation);
return FixItList{
{FixItHint::CreateRemoval(StarWithTrailWhitespace),
@@ -1218,12 +1232,12 @@ PointerDereferenceGadget::getFixits(const Strategy &S) const {
CharSourceRange derefRange = clang::CharSourceRange::getCharRange(
Op->getBeginLoc(), Op->getBeginLoc().getLocWithOffset(1));
// Inserts the [0]
- std::optional<SourceLocation> endOfOperand =
+ std::optional<SourceLocation> EndOfOperand =
getEndCharLoc(BaseDeclRefExpr, SM, Ctx.getLangOpts());
- if (endOfOperand) {
+ if (EndOfOperand) {
return FixItList{{FixItHint::CreateRemoval(derefRange),
FixItHint::CreateInsertion(
- endOfOperand.value().getLocWithOffset(1), "[0]")}};
+ (*EndOfOperand).getLocWithOffset(1), "[0]")}};
}
}
[[fallthrough]];
@@ -1248,10 +1262,12 @@ std::optional<FixItList> UPCStandalonePointerGadget::getFixits(const Strategy &S
ASTContext &Ctx = VD->getASTContext();
SourceManager &SM = Ctx.getSourceManager();
// Inserts the .data() after the DRE
- SourceLocation endOfOperand = getEndCharLoc(Node, SM, Ctx.getLangOpts());
+ std::optional<SourceLocation> EndOfOperand =
+ getPastLoc(Node, SM, Ctx.getLangOpts());
- return FixItList{{FixItHint::CreateInsertion(
- endOfOperand.getLocWithOffset(1), ".data()")}};
+ if (EndOfOperand)
+ return FixItList{{FixItHint::CreateInsertion(
+ *EndOfOperand, ".data()")}};
}
case Strategy::Kind::Wontfix:
case Strategy::Kind::Iterator:
@@ -1281,12 +1297,20 @@ fixUPCAddressofArraySubscriptWithSpan(const UnaryOperator *Node) {
if (auto ICE = Idx->getIntegerConstantExpr(Ctx))
if ((*ICE).isZero())
IdxIsLitZero = true;
+ std::optional<StringRef> DreString = getExprText(DRE, SM, LangOpts);
+ if (!DreString)
+ return std::nullopt;
+
if (IdxIsLitZero) {
// If the index is literal zero, we produce the most concise fix-it:
- SS << getExprText(DRE, SM, LangOpts).str() << ".data()";
+ SS << (*DreString).str() << ".data()";
} else {
- SS << "&" << getExprText(DRE, SM, LangOpts).str() << ".data()"
- << "[" << getExprText(Idx, SM, LangOpts).str() << "]";
+ std::optional<StringRef> IndexString = getExprText(Idx, SM, LangOpts);
+ if (!IndexString)
+ return std::nullopt;
+
+ SS << "&" << (*DreString).str() << ".data()"
+ << "[" << (*IndexString).str() << "]";
}
return FixItList{
FixItHint::CreateReplacement(Node->getSourceRange(), SS.str())};
@@ -1310,11 +1334,13 @@ std::optional<FixItList> UPCPreIncrementGadget::getFixits(const Strategy &S) con
// To transform UPC(++p) to UPC((p = p.subspan(1)).data()):
SS << "(" << varName.data() << " = " << varName.data()
<< ".subspan(1)).data()";
+ std::optional<SourceLocation> PreIncLocation =
+ getEndCharLoc(PreIncNode, Ctx.getSourceManager(), Ctx.getLangOpts());
+ if (!PreIncLocation)
+ return std::nullopt;
+
Fixes.push_back(FixItHint::CreateReplacement(
- SourceRange(PreIncNode->getBeginLoc(),
- getEndCharLoc(PreIncNode, Ctx.getSourceManager(),
- Ctx.getLangOpts())),
- SS.str()));
+ SourceRange(PreIncNode->getBeginLoc(), *PreIncLocation), SS.str()));
return Fixes;
}
}
@@ -1350,7 +1376,12 @@ populateInitializerFixItWithSpan(const Expr *Init, const ASTContext &Ctx,
// &`? It should. Maybe worth an NFC patch later.
Expr::NullPointerConstantValueDependence::
NPC_ValueDependentIsNotNull)) {
- SourceRange SR(Init->getBeginLoc(), getEndCharLoc(Init, SM, LangOpts));
+ std::optional<SourceLocation> InitLocation =
+ getEndCharLoc(Init, SM, LangOpts);
+ if (!InitLocation)
+ return {};
+
+ SourceRange SR(Init->getBeginLoc(), *InitLocation);
return {FixItHint::CreateRemoval(SR)};
}
@@ -1368,8 +1399,12 @@ populateInitializerFixItWithSpan(const Expr *Init, const ASTContext &Ctx,
// of `T`. So the extent is `n` unless `n` has side effects. Similar but
// simpler for the case where `Init` is `new T`.
if (const Expr *Ext = CxxNew->getArraySize().value_or(nullptr)) {
- if (!Ext->HasSideEffects(Ctx))
- ExtentText = getExprText(Ext, SM, LangOpts);
+ if (!Ext->HasSideEffects(Ctx)) {
+ std::optional<StringRef> ExtentString = getExprText(Ext, SM, LangOpts);
+ if (!ExtentString)
+ return {};
+ ExtentText = *ExtentString;
+ }
} else if (!CxxNew->isArray())
// Although the initializer is not allocating a buffer, the pointer
// variable could still be used in buffer access operations.
@@ -1392,12 +1427,15 @@ populateInitializerFixItWithSpan(const Expr *Init, const ASTContext &Ctx,
}
SmallString<32> StrBuffer{};
- SourceLocation LocPassInit = getPastLoc(Init, SM, LangOpts);
+ std::optional<SourceLocation> LocPassInit = getPastLoc(Init, SM, LangOpts);
+
+ if (!LocPassInit)
+ return {};
StrBuffer.append(", ");
StrBuffer.append(ExtentText);
StrBuffer.append("}");
- FixIts.push_back(FixItHint::CreateInsertion(LocPassInit, StrBuffer.str()));
+ FixIts.push_back(FixItHint::CreateInsertion(*LocPassInit, StrBuffer.str()));
return FixIts;
}
@@ -1420,7 +1458,7 @@ static FixItList fixVarDeclWithSpan(const VarDecl *D, const ASTContext &Ctx,
assert(!SpanEltT.isNull() && "Trying to fix a non-pointer type variable!");
FixItList FixIts{};
- SourceLocation
+ std::optional<SourceLocation>
ReplacementLastLoc; // the inclusive end location of the replacement
const SourceManager &SM = Ctx.getSourceManager();
@@ -1428,8 +1466,9 @@ static FixItList fixVarDeclWithSpan(const VarDecl *D, const ASTContext &Ctx,
FixItList InitFixIts =
populateInitializerFixItWithSpan(Init, Ctx, UserFillPlaceHolder);
- assert(!InitFixIts.empty() &&
- "Unable to fix initializer of unsafe variable declaration");
+ if (InitFixIts.empty())
+ return {};
+
// The loc right before the initializer:
ReplacementLastLoc = Init->getBeginLoc().getLocWithOffset(-1);
FixIts.insert(FixIts.end(), std::make_move_iterator(InitFixIts.begin()),
@@ -1442,8 +1481,12 @@ static FixItList fixVarDeclWithSpan(const VarDecl *D, const ASTContext &Ctx,
raw_svector_ostream OS(Replacement);
OS << "std::span<" << SpanEltT.getAsString() << "> " << D->getName();
+
+ if (!ReplacementLastLoc)
+ return {};
+
FixIts.push_back(FixItHint::CreateReplacement(
- SourceRange{D->getBeginLoc(), ReplacementLastLoc}, OS.str()));
+ SourceRange{D->getBeginLoc(), *ReplacementLastLoc}, OS.str()));
return FixIts;
}
diff --git a/clang/test/SemaCXX/warn-unsafe-buffer-usage-fixits-local-var-span.cpp b/clang/test/SemaCXX/warn-unsafe-buffer-usage-fixits-local-var-span.cpp
index ca3f7a4b172a8..cb6519a153fee 100644
--- a/clang/test/SemaCXX/warn-unsafe-buffer-usage-fixits-local-var-span.cpp
+++ b/clang/test/SemaCXX/warn-unsafe-buffer-usage-fixits-local-var-span.cpp
@@ -2,6 +2,8 @@
typedef int * Int_ptr_t;
typedef int Int_t;
+#define DEFINE_PTR(X) int* ptr = (X);
+
void local_array_subscript_simple() {
int tmp;
int *p = new int[10];
@@ -222,3 +224,28 @@ void unsupported_subscript_negative(int i, unsigned j, unsigned long k) {
tmp = r[j] + r[k]; // both `j` and `k` are unsigned so they must be non-negative
tmp = r[(unsigned int)-1]; // a cast-to-unsigned-expression is also non-negative
}
+
+void all_vars_in_macro() {
+ int* local;
+ DEFINE_PTR(local)
+ ptr[1] = 0;
+}
+
+void few_vars_in_macro() {
+ int* local;
+ DEFINE_PTR(local)
+ ptr[1] = 0;
+ int tmp;
+ ptr[2] = 30;
+ auto p = new int[10];
+ // CHECK-DAG: fix-it:"{{.*}}":{[[@LINE-1]]:3-[[@LINE-1]]:11}:"std::span<int> p"
+ // CHECK-DAG: fix-it:"{{.*}}":{[[@LINE-2]]:12-[[@LINE-2]]:12}:"{"
+ // CHECK-DAG: fix-it:"{{.*}}":{[[@LINE-3]]:23-[[@LINE-3]]:23}:", 10}"
+ tmp = p[5];
+ int val = *p;
+ // CHECK-DAG: fix-it:"{{.*}}":{[[@LINE-1]]:13-[[@LINE-1]]:14}:""
+ // CHECK-DAG: fix-it:"{{.*}}":{[[@LINE-2]]:15-[[@LINE-2]]:15}:"[0]"
+ val = *p + 30;
+ // CHECK-DAG: fix-it:"{{.*}}":{[[@LINE-1]]:9-[[@LINE-1]]:10}:""
+ // CHECK-DAG: fix-it:"{{.*}}":{[[@LINE-2]]:11-[[@LINE-2]]:11}:"[0]"
+}
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