[clang] [clang][analyzer] Add C standard streams to the internal memory space (PR #147766)

[Balazs Benics via cfe-commits]

=?utf-8?q?Balázs_Kéri?= <balazs.keri at ericsson.com>
Message-ID:
In-Reply-To: <llvm.org/llvm/llvm-project/pull/147766 at github.com>


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@@ -1054,10 +1054,26 @@ const VarRegion *MemRegionManager::getVarRegion(const VarDecl *D,
     assert(!Ty.isNull());
     if (Ty.isConstQualified()) {
       sReg = getGlobalsRegion(MemRegion::GlobalImmutableSpaceRegionKind);
-    } else if (Ctx.getSourceManager().isInSystemHeader(D->getLocation())) {
-      sReg = getGlobalsRegion(MemRegion::GlobalSystemSpaceRegionKind);
     } else {
-      sReg = getGlobalsRegion(MemRegion::GlobalInternalSpaceRegionKind);
+      StringRef N = D->getNameAsString();
+      QualType FILETy = D->getASTContext().getFILEType();
+      if (!FILETy.isNull())
+        FILETy = FILETy.getCanonicalType();
+      Ty = Ty.getCanonicalType();
+      bool IsStdStreamVar = Ty->isPointerType() &&
+                            Ty->getPointeeType() == FILETy &&
+                            (N == "stdin" || N == "stdout" || N == "stderr");
+      // Pointer value of C standard streams is usually not modified by calls
+      // to functions declared in system headers. This means that they should
+      // not get invalidated by calls to functions declared in system headers,
+      // so they are placed in the global internal space, which is not
+      // invalidated by calls to functions declared in system headers.
+      if (Ctx.getSourceManager().isInSystemHeader(D->getLocation()) &&
+          !IsStdStreamVar) {
+        sReg = getGlobalsRegion(MemRegion::GlobalSystemSpaceRegionKind);
+      } else {
+        sReg = getGlobalsRegion(MemRegion::GlobalInternalSpaceRegionKind);
+      }
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steakhal wrote:

I'm not challenging this.

https://github.com/llvm/llvm-project/pull/147766