[clang] [analyzer] Fix FP for cplusplus.placement new #149240 (PR #150161)

[Balazs Benics via cfe-commits]

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@@ -111,32 +111,14 @@ bool PlacementNewChecker::checkPlaceCapacityIsSufficient(
   if (!SizeOfPlaceCI)
     return true;
 
-  if ((SizeOfPlaceCI->getValue() < SizeOfTargetCI->getValue()) ||
-      (IsArrayTypeAllocated &&
-       SizeOfPlaceCI->getValue() >= SizeOfTargetCI->getValue())) {
+  if ((SizeOfPlaceCI->getValue() < SizeOfTargetCI->getValue())) {
     if (ExplodedNode *N = C.generateErrorNode(C.getState())) {
       std::string Msg;
       // TODO: use clang constant
-      if (IsArrayTypeAllocated &&
-          SizeOfPlaceCI->getValue() > SizeOfTargetCI->getValue())
-        Msg = std::string(llvm::formatv(
-            "{0} bytes is possibly not enough for array allocation which "
-            "requires {1} bytes. Current overhead requires the size of {2} "
-            "bytes",
-            SizeOfPlaceCI->getValue(), SizeOfTargetCI->getValue(),
-            *SizeOfPlaceCI->getValue() - SizeOfTargetCI->getValue()));
-      else if (IsArrayTypeAllocated &&
-               SizeOfPlaceCI->getValue() == SizeOfTargetCI->getValue())
-        Msg = std::string(llvm::formatv(
-            "Storage provided to placement new is only {0} bytes, "
-            "whereas the allocated array type requires more space for "
-            "internal needs",
-            SizeOfPlaceCI->getValue()));
-      else
-        Msg = std::string(llvm::formatv(
-            "Storage provided to placement new is only {0} bytes, "
-            "whereas the allocated type requires {1} bytes",
-            SizeOfPlaceCI->getValue(), SizeOfTargetCI->getValue()));
+      Msg = std::string(
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steakhal wrote:

You could at this point just initialize `Msg` with this.
You also should not need to call the `std::string` explicit conversion operator.

https://github.com/llvm/llvm-project/pull/150161