Fix failing 3C test for Windows (checkedc#956)

* Include stddef.h where size_t is needed

* Fix io redirection issues for windows

* Add more null checks to extractBaseType

This should resolve tests failing on windows due to null type location

* Add `#include <cctype>` to a file that uses `std::tolower`.

Hope this fixes a Windows build failure reported by Mandeep.

* Add null check to getSourceRange

This avoids an assertion fail on some windows header files.

* Change IO redirections to work on windows

* Disable 3C extstructfields test on Windows again.

Windows doesn't have sigaction, and we couldn't find a reasonable
alternative.

* Add -base-dir to 3c commands in *rewrite_header tests.

This is the same workaround used in many other tests for a
Windows-specific problem where 3C thinks it isn't allowed to write a
file because (1) it isn't under the base dir (which defaults to
something under the build directory) and (2) the backslash in the
canonicalized file path doesn't match the hard-coded forward slash in
the RUN command.  We should probably fix this silly problem a better
way, but first we may as well apply the workaround we already have.

While I'm here, replace --output-postfix with -output-postfix for
consistency with the other tests.

* rewrite_header.c: Remove %S\ from replacement of sed substitution.

`#include "rewrite_header.checked.h"` will work just fine to include a
file in the same directory, and %S caused a problem on Windows when it
expanded to a file path including "\3C" and the \3 was interpreted as a
regular expression backreference.

* rewrite_header: Avoid `sed -i`.

The GnuWin32 `sed -i` has a bug where it leaves its temporary file
behind, and there's no known solution other than to not use it.

* Fix root_cause.c test for windows

A conditional in Constraints.cpp checked if the first character of a
file path was "/" to determine if the path was absolute, but on windows,
an absolute path will start with "C:\".

Co-authored-by: Matt McCutchen (Correct Computation) <[email protected]>

Author: john-h-kastner

clang/include/clang/3C/ConstraintVariables.h

@@ -228,11 +228,19 @@ class PointerVariableConstraint : public ConstraintVariable {
   void addArrayAnnotations(std::stack<std::string> &CheckedArrs,
                            std::deque<std::string> &EndStrs) const;
 
-  // Utility used by the constructor to extract string representation of the
-  // base type that preserves macros where possible.
+  // Utility used by the constructor to obtain a string representation of a
+  // declaration's base type. To preserve macros, this we first try to take
+  // the type directly from source code. Where that is not possible, the type
+  // is regenerated from the type in the clang AST.
   static std::string extractBaseType(DeclaratorDecl *D, QualType QT,
                                      const Type *Ty, const ASTContext &C);
 
+  // Try to extract string representation of the base type for a declaration
+  // from the source code. If the base type cannot be extracted from source, an
+  // empty string is returned instead.
+  static std::string tryExtractBaseType(DeclaratorDecl *D, QualType QT,
+                                        const Type *Ty, const ASTContext &C);
+
   // Flag to indicate that this constraint is a part of function prototype
   // e.g., Parameters or Return.
   bool PartOfFuncPrototype;

clang/include/clang/3C/RewriteUtils.h

@@ -88,13 +88,14 @@ class FunctionDeclReplacement
 
   SourceRange getSourceRange(SourceManager &SM) const override {
     TypeSourceInfo *TSInfo = Decl->getTypeSourceInfo();
-    if (!TSInfo)
+    FunctionTypeLoc TypeLoc;
+    if (TSInfo) {
+      auto TSInfoLoc = TSInfo->getTypeLoc();
+      TypeLoc = getBaseTypeLoc(TSInfoLoc).getAs<clang::FunctionTypeLoc>();
+    }
+    if (!TSInfo || TypeLoc.isNull())
       return SourceRange(Decl->getBeginLoc(),
                          getFunctionDeclarationEnd(Decl, SM));
-    FunctionTypeLoc TypeLoc =
-        getBaseTypeLoc(TSInfo->getTypeLoc()).getAs<clang::FunctionTypeLoc>();
-
-    assert("FunctionDecl doesn't have function type?" && !TypeLoc.isNull());
 
     // Function pointer are funky, and require special handling to rewrite the
     // return type.

clang/lib/3C/ArrayBoundsInferenceConsumer.cpp

@@ -15,6 +15,7 @@
 #include "clang/3C/ConstraintResolver.h"
 #include "clang/Analysis/Analyses/Dominators.h"
 #include "clang/Analysis/CFG.h"
+#include <cctype>
 #include <sstream>
 
 static std::set<std::string> LengthVarNamesPrefixes = {"len", "count", "size",

clang/lib/3C/ConstraintVariables.cpp

@@ -391,11 +391,10 @@ PointerVariableConstraint::PointerVariableConstraint(
   }
 }
 
-std::string PointerVariableConstraint::extractBaseType(DeclaratorDecl *D,
-                                                       QualType QT,
-                                                       const Type *Ty,
-                                                       const ASTContext &C) {
-  std::string BaseTypeStr;
+std::string PointerVariableConstraint::tryExtractBaseType(DeclaratorDecl *D,
+                                                          QualType QT,
+                                                          const Type *Ty,
+                                                          const ASTContext &C) {
   bool FoundBaseTypeInSrc = false;
   if (!QT->isOrContainsCheckedType() && !Ty->getAs<TypedefType>() && D &&
       D->getTypeSourceInfo()) {
@@ -406,32 +405,33 @@ std::string PointerVariableConstraint::extractBaseType(DeclaratorDecl *D,
       TL = getBaseTypeLoc(TL).getAs<FunctionTypeLoc>();
       // FunctionDecl that doesn't have function type? weird
       if (TL.isNull())
-        FoundBaseTypeInSrc = false;
-      else
-        TL = TL.getAs<clang::FunctionTypeLoc>().getReturnLoc();
+        return "";
+      TL = TL.getAs<clang::FunctionTypeLoc>().getReturnLoc();
     } else {
       FoundBaseTypeInSrc = D->getType() == QT;
     }
-    TypeLoc BaseLoc = getBaseTypeLoc(TL);
-    if (!BaseLoc.getAs<TypedefTypeLoc>().isNull()) {
-      FoundBaseTypeInSrc = false;
-    } else {
-      // Only use this type if the type passed as a parameter to this
-      // constructor agrees with the actual type of the declaration.
-      SourceRange SR = BaseLoc.getSourceRange();
-      if (FoundBaseTypeInSrc && SR.isValid()) {
-        BaseTypeStr = getSourceText(SR, C);
-
-        // getSourceText returns the empty string when there's a pointer level
-        // inside a macro. Not sure how to handle this, so fall back to tyToStr.
-        if (BaseTypeStr.empty())
-          FoundBaseTypeInSrc = false;
-      } else
-        FoundBaseTypeInSrc = false;
+    if (!TL.isNull()) {
+      TypeLoc BaseLoc = getBaseTypeLoc(TL);
+      // Only proceed if the base type location is not null, amd it is not a
+      // typedef type location.
+      if (!BaseLoc.isNull() && BaseLoc.getAs<TypedefTypeLoc>().isNull()) {
+        SourceRange SR = BaseLoc.getSourceRange();
+        if (FoundBaseTypeInSrc && SR.isValid())
+          return getSourceText(SR, C);
+      }
     }
   }
+
+  return "";
+}
+
+std::string PointerVariableConstraint::extractBaseType(DeclaratorDecl *D,
+                                                       QualType QT,
+                                                       const Type *Ty,
+                                                       const ASTContext &C) {
+  std::string BaseTypeStr = tryExtractBaseType(D, QT, Ty, C);
   // Fall back to rebuilding the base type based on type passed to constructor
-  if (!FoundBaseTypeInSrc)
+  if (BaseTypeStr.empty())
     BaseTypeStr = tyToStr(Ty);
 
   return BaseTypeStr;

clang/lib/3C/Constraints.cpp

@@ -611,7 +611,7 @@ Geq *Constraints::createGeq(Atom *Lhs, Atom *Rhs, const std::string &Rsn,
   if (PL != nullptr && PL->valid()) {
     // Make this invalid, if the source location is not absolute path
     // this is to avoid crashes in clangd.
-    if (PL->getFileName().c_str()[0] != '/')
+    if (!llvm::sys::path::is_absolute(PL->getFileName()))
       PL = nullptr;
   }
   assert("Shouldn't be constraining WILD >= VAR" && Lhs != getWild());

clang/lib/3C/Utils.cpp

@@ -411,6 +411,7 @@ bool isZeroBoundsExpr(BoundsExpr *BE, const ASTContext &C) {
 }
 
 TypeLoc getBaseTypeLoc(TypeLoc T) {
+  assert(!T.isNull() && "Can't get base location from Null.");
   while (!T.getNextTypeLoc().isNull() &&
          (!T.getAs<ParenTypeLoc>().isNull() ||
           T.getTypePtr()->isPointerType() || T.getTypePtr()->isArrayType()))

clang/test/3C/3d-allocation.c

@@ -1,4 +1,3 @@
-// UNSUPPORTED: system-windows
 // RUN: 3c -alltypes -addcr %s -- | FileCheck -match-full-lines -check-prefixes="CHECK_ALL","CHECK" %s
 // RUN: 3c -addcr %s -- | FileCheck -match-full-lines -check-prefixes="CHECK_NOALL","CHECK" %s
 // RUN: 3c -addcr %s -- | %clang -c -fcheckedc-extension -x c -o /dev/null -

clang/test/3C/basic.c

@@ -1,4 +1,3 @@
-// UNSUPPORTED: system-windows
 // RUN: 3c -alltypes %s -- | FileCheck -match-full-lines -check-prefixes="CHECK_ALL","CHECK" %s
 // RUN: 3c %s -- | FileCheck -match-full-lines -check-prefixes="CHECK_NOALL","CHECK" %s
 // RUN: 3c %s -- | %clang -c -fcheckedc-extension -x c -o /dev/null -

clang/test/3C/definedType.c

@@ -1,12 +1,11 @@
-// UNSUPPORTED: system-windows
 // RUN: 3c -addcr -alltypes %s -- | FileCheck -match-full-lines -check-prefixes="CHECK_ALL","CHECK" %s
 // RUN: 3c -addcr %s -- | FileCheck -match-full-lines -check-prefixes="CHECK_NOALL","CHECK" %s
 // RUN: 3c -addcr %s -- | %clang -c -fcheckedc-extension -x c -o /dev/null -
 // RUN: 3c -alltypes -output-postfix=checked %s
 // RUN: 3c -alltypes %S/definedType.checked.c -- | count 0
 // RUN: rm %S/definedType.checked.c
 
-#define size_t unsigned long
+#include <stddef.h>
 _Itype_for_any(T) void *malloc(size_t size) : itype(_Array_ptr<T>) byte_count(size);
 
 // From issue 204

clang/test/3C/dont_rewrite_header.c

@@ -1,9 +1,8 @@
-// UNSUPPORTED: system-windows
-// RUN: 3c -alltypes -addcr --output-postfix=checked %S/dont_rewrite_header.c %S/dont_rewrite_header.h
-// RUN: FileCheck -match-full-lines -check-prefixes="CHECK" %S/dont_rewrite_header.checked.c < %S/dont_rewrite_header.checked.c
+// RUN: 3c -base-dir=%S -alltypes -addcr -output-postfix=checked %S/dont_rewrite_header.c %S/dont_rewrite_header.h
+// RUN: FileCheck -match-full-lines -check-prefixes="CHECK" %S/dont_rewrite_header.checked.c --input-file %S/dont_rewrite_header.checked.c
 // RUN: test ! -f %S/dont_rewrite_header.checked.h
 // RUN: %clang -c -fcheckedc-extension -x c -o /dev/null %S/dont_rewrite_header.checked.c
-// RUN: 3c -alltypes -addcr --output-postfix=checked2 %S/dont_rewrite_header.checked.c %S/dont_rewrite_header.h
+// RUN: 3c -base-dir=%S -alltypes -addcr --output-postfix=checked2 %S/dont_rewrite_header.checked.c %S/dont_rewrite_header.h
 // RUN: test ! -f %S/dont_rewrite_header.checked.checked2.h -a ! -f %S/dont_rewrite_header.checked.checked2.c
 // RUN: rm %S/dont_rewrite_header.checked.c