[-Wunsafe-buffer-usage] Fix assert when constexpr size passed to snprintf() (#119786) #124022
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…intf() (llvm#119786) EvaluateAsConstExpr() can return an lvalue which is not compatible with a subsequent getInt() call. Instead, use EvaluateAsInt() which will use all techniques availble to get an int result compatible with the subsequent getInt() call.
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@llvm/pr-subscribers-clang-analysis @llvm/pr-subscribers-clang Author: Thomas Sepez (tsepez) ChangesEvaluateAsConstExpr() can return an lvalue which is not compatible Full diff: https://github.com/llvm/llvm-project/pull/124022.diff 1 Files Affected:
diff --git a/clang/lib/Analysis/UnsafeBufferUsage.cpp b/clang/lib/Analysis/UnsafeBufferUsage.cpp
index c064aa30e8aedc..c51398698922bf 100644
--- a/clang/lib/Analysis/UnsafeBufferUsage.cpp
+++ b/clang/lib/Analysis/UnsafeBufferUsage.cpp
@@ -930,7 +930,7 @@ AST_MATCHER(CallExpr, hasUnsafeSnprintfBuffer) {
// The array element type must be compatible with `char` otherwise an
// explicit cast will be needed, which will make this check unreachable.
// Therefore, the array extent is same as its' bytewise size.
- if (Size->EvaluateAsConstantExpr(ER, Ctx)) {
+ if (Size->EvaluateAsInt(ER, Ctx)) {
APSInt EVal = ER.Val.getInt(); // Size must have integer type
return APSInt::compareValues(EVal, APSInt(CAT->getSize(), true)) != 0;
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Ping |
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@ziqingluo-90 can you take a look? |
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See the analysis in #119786 |
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…intf() (llvm#119786) (llvm#124022) EvaluateAsConstExpr() can return an lvalue which is not compatible with a subsequent getInt() call. Instead, use EvaluateAsInt() which will use all techniques availble to get an int result compatible with the subsequent getInt() call.
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Sure, I'll back-fill the tests shortly. |
Thanks for reminding us of the test. |
…intf() (llvm#119786) (llvm#124022) EvaluateAsConstExpr() can return an lvalue which is not compatible with a subsequent getInt() call. Instead, use EvaluateAsInt() which will use all techniques availble to get an int result compatible with the subsequent getInt() call.
…intf() (llvm#119786) (llvm#124022) EvaluateAsConstExpr() can return an lvalue which is not compatible with a subsequent getInt() call. Instead, use EvaluateAsInt() which will use all techniques availble to get an int result compatible with the subsequent getInt() call.
EvaluateAsConstExpr() can return an lvalue which is not compatible
with a subsequent getInt() call. Instead, use EvaluateAsInt() which
will use all techniques availble to get an int result compatible
with the subsequent getInt() call.