diff --git a/cpp/ql/src/Critical/OverflowStatic.ql b/cpp/ql/src/Critical/OverflowStatic.ql
index 13a4fb6bcb76..f11ebdd77b15 100644
--- a/cpp/ql/src/Critical/OverflowStatic.ql
+++ b/cpp/ql/src/Critical/OverflowStatic.ql
@@ -56,7 +56,8 @@ predicate overflowOffsetInLoop(BufferAccess bufaccess, string msg) {
     loop.limit() >= bufaccess.bufferSize() and
     loop.counter().getAnAccess() = bufaccess.getArrayOffset() and
     // Ensure that we don't have an upper bound on the array index that's less than the buffer size.
-    not upperBound(bufaccess.getArrayOffset().getFullyConverted()) < bufaccess.bufferSize() and
+    not upperBound(bufaccess.getArrayOffset().getFullyConverted()) <
+      bufaccess.bufferSize().toBigInt() and
     // The upper bounds analysis must not have been widended
     not upperBoundMayBeWidened(bufaccess.getArrayOffset().getFullyConverted()) and
     msg =
@@ -101,7 +102,7 @@ class CallWithBufferSize extends FunctionCall {
     )
   }
 
-  int statedSizeValue() {
+  QlBuiltins::BigInt statedSizeValue() {
     // `upperBound(e)` defaults to `exprMaxVal(e)` when `e` isn't analyzable. So to get a meaningful
     // result in this case we pick the minimum value obtainable from dataflow and range analysis.
     result =
@@ -109,16 +110,16 @@ class CallWithBufferSize extends FunctionCall {
           .minimum(min(Expr statedSizeSrc |
               DataFlow::localExprFlow(statedSizeSrc, this.statedSizeExpr())
             |
-              statedSizeSrc.getValue().toInt()
+              statedSizeSrc.getValue().toBigInt()
             ))
   }
 }
 
 predicate wrongBufferSize(Expr error, string msg) {
-  exists(CallWithBufferSize call, int bufsize, Variable buf, int statedSize |
+  exists(CallWithBufferSize call, int bufsize, Variable buf, QlBuiltins::BigInt statedSize |
     staticBuffer(call.buffer(), buf, bufsize) and
     statedSize = call.statedSizeValue() and
-    statedSize > bufsize and
+    statedSize > bufsize.toBigInt() and
     error = call.statedSizeExpr() and
     msg =
       "Potential buffer-overflow: '" + buf.getName() + "' has size " + bufsize.toString() + " not " +
diff --git a/cpp/ql/src/Likely Bugs/Arithmetic/IntMultToLong.ql b/cpp/ql/src/Likely Bugs/Arithmetic/IntMultToLong.ql
index ba7a6b58aa01..29cd160cad4f 100644
--- a/cpp/ql/src/Likely Bugs/Arithmetic/IntMultToLong.ql	
+++ b/cpp/ql/src/Likely Bugs/Arithmetic/IntMultToLong.ql	
@@ -76,20 +76,22 @@ int getEffectiveMulOperands(MulExpr me) {
  * using SimpleRangeAnalysis.
  */
 class AnalyzableExpr extends Expr {
-  float maxValue() { result = upperBound(this.getFullyConverted()) }
+  QlBuiltins::BigInt maxValue() { result = upperBound(this.getFullyConverted()) }
 
-  float minValue() { result = lowerBound(this.getFullyConverted()) }
+  QlBuiltins::BigInt minValue() { result = lowerBound(this.getFullyConverted()) }
 }
 
 class ParenAnalyzableExpr extends AnalyzableExpr, ParenthesisExpr {
-  override float maxValue() { result = this.getExpr().(AnalyzableExpr).maxValue() }
+  override QlBuiltins::BigInt maxValue() { result = this.getExpr().(AnalyzableExpr).maxValue() }
 
-  override float minValue() { result = this.getExpr().(AnalyzableExpr).minValue() }
+  override QlBuiltins::BigInt minValue() { result = this.getExpr().(AnalyzableExpr).minValue() }
 }
 
 class MulAnalyzableExpr extends AnalyzableExpr, MulExpr {
-  override float maxValue() {
-    exists(float x1, float y1, float x2, float y2 |
+  override QlBuiltins::BigInt maxValue() {
+    exists(
+      QlBuiltins::BigInt x1, QlBuiltins::BigInt y1, QlBuiltins::BigInt x2, QlBuiltins::BigInt y2
+    |
       x1 = this.getLeftOperand().getFullyConverted().(AnalyzableExpr).minValue() and
       x2 = this.getLeftOperand().getFullyConverted().(AnalyzableExpr).maxValue() and
       y1 = this.getRightOperand().getFullyConverted().(AnalyzableExpr).minValue() and
@@ -98,8 +100,10 @@ class MulAnalyzableExpr extends AnalyzableExpr, MulExpr {
     )
   }
 
-  override float minValue() {
-    exists(float x1, float x2, float y1, float y2 |
+  override QlBuiltins::BigInt minValue() {
+    exists(
+      QlBuiltins::BigInt x1, QlBuiltins::BigInt x2, QlBuiltins::BigInt y1, QlBuiltins::BigInt y2
+    |
       x1 = this.getLeftOperand().getFullyConverted().(AnalyzableExpr).minValue() and
       x2 = this.getLeftOperand().getFullyConverted().(AnalyzableExpr).maxValue() and
       y1 = this.getRightOperand().getFullyConverted().(AnalyzableExpr).minValue() and
@@ -110,13 +114,13 @@ class MulAnalyzableExpr extends AnalyzableExpr, MulExpr {
 }
 
 class AddAnalyzableExpr extends AnalyzableExpr, AddExpr {
-  override float maxValue() {
+  override QlBuiltins::BigInt maxValue() {
     result =
       this.getLeftOperand().getFullyConverted().(AnalyzableExpr).maxValue() +
         this.getRightOperand().getFullyConverted().(AnalyzableExpr).maxValue()
   }
 
-  override float minValue() {
+  override QlBuiltins::BigInt minValue() {
     result =
       this.getLeftOperand().getFullyConverted().(AnalyzableExpr).minValue() +
         this.getRightOperand().getFullyConverted().(AnalyzableExpr).minValue()
@@ -124,13 +128,13 @@ class AddAnalyzableExpr extends AnalyzableExpr, AddExpr {
 }
 
 class SubAnalyzableExpr extends AnalyzableExpr, SubExpr {
-  override float maxValue() {
+  override QlBuiltins::BigInt maxValue() {
     result =
       this.getLeftOperand().getFullyConverted().(AnalyzableExpr).maxValue() -
         this.getRightOperand().getFullyConverted().(AnalyzableExpr).minValue()
   }
 
-  override float minValue() {
+  override QlBuiltins::BigInt minValue() {
     result =
       this.getLeftOperand().getFullyConverted().(AnalyzableExpr).minValue() -
         this.getRightOperand().getFullyConverted().(AnalyzableExpr).maxValue()
@@ -140,7 +144,7 @@ class SubAnalyzableExpr extends AnalyzableExpr, SubExpr {
 class VarAnalyzableExpr extends AnalyzableExpr, VariableAccess {
   VarAnalyzableExpr() { this.getTarget() instanceof StackVariable }
 
-  override float maxValue() {
+  override QlBuiltins::BigInt maxValue() {
     exists(SsaDefinition def, Variable v |
       def.getAUse(v) = this and
       // if there is a defining expression, use that for
@@ -152,7 +156,7 @@ class VarAnalyzableExpr extends AnalyzableExpr, VariableAccess {
     )
   }
 
-  override float minValue() {
+  override QlBuiltins::BigInt minValue() {
     exists(SsaDefinition def, Variable v |
       def.getAUse(v) = this and
       if exists(def.getDefiningValue(v))
diff --git a/cpp/ql/src/Likely Bugs/Arithmetic/PointlessComparison.ql b/cpp/ql/src/Likely Bugs/Arithmetic/PointlessComparison.ql
index e2fe02be867f..991fc258d30b 100644
--- a/cpp/ql/src/Likely Bugs/Arithmetic/PointlessComparison.ql	
+++ b/cpp/ql/src/Likely Bugs/Arithmetic/PointlessComparison.ql	
@@ -26,7 +26,9 @@ import UnsignedGEZero
 // So to reduce the number of false positives, we do not report a result if
 // the comparison is in a macro expansion. Similarly for template
 // instantiations.
-from ComparisonOperation cmp, SmallSide ss, float left, float right, boolean value, string reason
+from
+  ComparisonOperation cmp, SmallSide ss, QlBuiltins::BigInt left, QlBuiltins::BigInt right,
+  boolean value, string reason
 where
   not cmp.isInMacroExpansion() and
   not cmp.isFromTemplateInstantiation(_) and
diff --git a/cpp/ql/src/Security/CWE/CWE-190/ComparisonWithWiderType.ql b/cpp/ql/src/Security/CWE/CWE-190/ComparisonWithWiderType.ql
index 7d9ef88adea1..a6402d7791e9 100644
--- a/cpp/ql/src/Security/CWE/CWE-190/ComparisonWithWiderType.ql
+++ b/cpp/ql/src/Security/CWE/CWE-190/ComparisonWithWiderType.ql
@@ -58,7 +58,8 @@ where
     // We adjust the comparison size in the case of a signed integer type.
     // This is to exclude the sign bit from the comparison that determines if the small type's size is sufficient to hold
     // the value of the larger type determined with range analysis.
-    upperBound(conv).log2() > (getComparisonSize(small) * 8 - getComparisonSizeAdjustment(small))
+    upperBound(conv).toString().length() / 10.log() >
+      (getComparisonSize(small) * 8 - getComparisonSizeAdjustment(small))
   ) and
   // Ignore cases where the smaller type is int or larger
   // These are still bugs, but you should need a very large string or array to
diff --git a/cpp/ql/src/Security/CWE/CWE-191/UnsignedDifferenceExpressionComparedZero.ql b/cpp/ql/src/Security/CWE/CWE-191/UnsignedDifferenceExpressionComparedZero.ql
index 5f7d88e9a716..973523b6fcd5 100644
--- a/cpp/ql/src/Security/CWE/CWE-191/UnsignedDifferenceExpressionComparedZero.ql
+++ b/cpp/ql/src/Security/CWE/CWE-191/UnsignedDifferenceExpressionComparedZero.ql
@@ -57,20 +57,20 @@ predicate exprIsSubLeftOrLess(SubExpr sub, DataFlow::Node n) {
       isGuarded(sub, other.asExpr(), n.asExpr()) // other >= n
     )
     or
-    exists(DataFlow::Node other, float p, float q |
+    exists(DataFlow::Node other, QlBuiltins::BigInt p, QlBuiltins::BigInt q |
       // linear access of `other`
       exprIsSubLeftOrLess(sub, other) and
       linearAccess(n.asExpr(), other.asExpr(), p, q) and // n = p * other + q
-      p <= 1 and
-      q <= 0
+      p <= 1.toBigInt() and
+      q <= 0.toBigInt()
     )
     or
-    exists(DataFlow::Node other, float p, float q |
+    exists(DataFlow::Node other, QlBuiltins::BigInt p, QlBuiltins::BigInt q |
       // linear access of `n`
       exprIsSubLeftOrLess(sub, other) and
       linearAccess(other.asExpr(), n.asExpr(), p, q) and // other = p * n + q
-      p >= 1 and
-      q >= 0
+      p >= 1.toBigInt() and
+      q >= 0.toBigInt()
     )
   )
 }
diff --git a/cpp/ql/src/experimental/Likely Bugs/DerefNullResult.cpp b/cpp/ql/src/experimental/Likely Bugs/DerefNullResult.cpp
index f96d67517b75..787019bb3abf 100644
--- a/cpp/ql/src/experimental/Likely Bugs/DerefNullResult.cpp	
+++ b/cpp/ql/src/experimental/Likely Bugs/DerefNullResult.cpp	
@@ -1,3 +1,8 @@
+#define NULL nullptr
+char *malloc(int);
+void printf(const char *, ...);
+int snprintf(char *, int, const char *);
+
 char * create (int arg) {
     if (arg > 42) {
         // this function may return NULL
diff --git a/cpp/ql/src/experimental/Likely Bugs/RedundantNullCheckParam.cpp b/cpp/ql/src/experimental/Likely Bugs/RedundantNullCheckParam.cpp
index 3765d0b14d40..7b9aa815d464 100644
--- a/cpp/ql/src/experimental/Likely Bugs/RedundantNullCheckParam.cpp	
+++ b/cpp/ql/src/experimental/Likely Bugs/RedundantNullCheckParam.cpp	
@@ -1,3 +1,5 @@
+#define NULL nullptr
+
 void test(char *arg1, int *arg2) {
     if (arg1[0] == 'A') {
         if (arg2 != NULL) { //maybe redundant
diff --git a/cpp/ql/src/experimental/Security/CWE/CWE-561/FindIncorrectlyUsedSwitch.ql b/cpp/ql/src/experimental/Security/CWE/CWE-561/FindIncorrectlyUsedSwitch.ql
index a643c3e3bf08..b006d773a248 100644
--- a/cpp/ql/src/experimental/Security/CWE/CWE-561/FindIncorrectlyUsedSwitch.ql
+++ b/cpp/ql/src/experimental/Security/CWE/CWE-561/FindIncorrectlyUsedSwitch.ql
@@ -28,32 +28,32 @@ predicate isRealRange(Expr exp) {
   lowerBound(exp).toString() != "-4294967296" and
   lowerBound(exp).toString() != "-Infinity" and
   lowerBound(exp).toString() != "NaN" and
-  upperBound(exp) != 2147483647 and
-  upperBound(exp) != 268435455 and
-  upperBound(exp) != 33554431 and
-  upperBound(exp) != 8388607 and
-  upperBound(exp) != 65535 and
-  upperBound(exp) != 32767 and
-  upperBound(exp) != 255 and
-  upperBound(exp) != 127 and
-  upperBound(exp) != 63 and
-  upperBound(exp) != 31 and
-  upperBound(exp) != 15 and
-  upperBound(exp) != 7 and
-  lowerBound(exp) != -2147483648 and
-  lowerBound(exp) != -268435456 and
-  lowerBound(exp) != -33554432 and
-  lowerBound(exp) != -8388608 and
-  lowerBound(exp) != -65536 and
-  lowerBound(exp) != -32768 and
-  lowerBound(exp) != -128
+  upperBound(exp) != 2147483647.toBigInt() and
+  upperBound(exp) != 268435455.toBigInt() and
+  upperBound(exp) != 33554431.toBigInt() and
+  upperBound(exp) != 8388607.toBigInt() and
+  upperBound(exp) != 65535.toBigInt() and
+  upperBound(exp) != 32767.toBigInt() and
+  upperBound(exp) != 255.toBigInt() and
+  upperBound(exp) != 127.toBigInt() and
+  upperBound(exp) != 63.toBigInt() and
+  upperBound(exp) != 31.toBigInt() and
+  upperBound(exp) != 15.toBigInt() and
+  upperBound(exp) != 7.toBigInt() and
+  lowerBound(exp) != "-2147483648".toBigInt() and
+  lowerBound(exp) != -268435456.toBigInt() and
+  lowerBound(exp) != -33554432.toBigInt() and
+  lowerBound(exp) != -8388608.toBigInt() and
+  lowerBound(exp) != -65536.toBigInt() and
+  lowerBound(exp) != -32768.toBigInt() and
+  lowerBound(exp) != -128.toBigInt()
 }
 
 /** Holds if the range of values for the condition is less than the choices. */
 predicate isNotAllSelected(SwitchStmt swtmp) {
   not swtmp.getExpr().isConstant() and
-  exists(int i |
-    i != 0 and
+  exists(QlBuiltins::BigInt i |
+    i != 0.toBigInt() and
     (
       i = lowerBound(swtmp.getASwitchCase().getExpr()) and
       upperBound(swtmp.getExpr()) < i
@@ -70,7 +70,7 @@ predicate isNotAllSelected(SwitchStmt swtmp) {
 /** Holds if the range of values for the condition is greater than the selection. */
 predicate isConditionBig(SwitchStmt swtmp) {
   not swtmp.hasDefaultCase() and
-  not exists(int iu, int il |
+  not exists(QlBuiltins::BigInt iu, QlBuiltins::BigInt il |
     (
       iu = upperBound(swtmp.getASwitchCase().getExpr()) or
       iu = upperBound(swtmp.getASwitchCase().getEndExpr())
@@ -130,7 +130,7 @@ from SwitchStmt sw, string msg
 where
   isRealRange(sw.getExpr()) and
   lowerBound(sw.getExpr()) != upperBound(sw.getExpr()) and
-  lowerBound(sw.getExpr()) != 0 and
+  lowerBound(sw.getExpr()) != 0.toBigInt() and
   not exists(Expr cexp |
     cexp = sw.getASwitchCase().getExpr() and not isRealRange(cexp)
     or
diff --git a/cpp/ql/src/experimental/Security/CWE/CWE-783/OperatorPrecedenceLogicErrorWhenUseBitwiseOrLogicalOperations.ql b/cpp/ql/src/experimental/Security/CWE/CWE-783/OperatorPrecedenceLogicErrorWhenUseBitwiseOrLogicalOperations.ql
index 8bb1d0ba97bf..e0abfbefaf93 100644
--- a/cpp/ql/src/experimental/Security/CWE/CWE-783/OperatorPrecedenceLogicErrorWhenUseBitwiseOrLogicalOperations.ql
+++ b/cpp/ql/src/experimental/Security/CWE/CWE-783/OperatorPrecedenceLogicErrorWhenUseBitwiseOrLogicalOperations.ql
@@ -97,24 +97,24 @@ predicate isRealRange(Expr exp) {
   lowerBound(exp).toString() != "-4294967296" and
   lowerBound(exp).toString() != "-Infinity" and
   lowerBound(exp).toString() != "NaN" and
-  upperBound(exp) != 2147483647 and
-  upperBound(exp) != 268435455 and
-  upperBound(exp) != 33554431 and
-  upperBound(exp) != 8388607 and
-  upperBound(exp) != 65535 and
-  upperBound(exp) != 32767 and
-  upperBound(exp) != 255 and
-  upperBound(exp) != 127 and
-  lowerBound(exp) != -2147483648 and
-  lowerBound(exp) != -268435456 and
-  lowerBound(exp) != -33554432 and
-  lowerBound(exp) != -8388608 and
-  lowerBound(exp) != -65536 and
-  lowerBound(exp) != -32768 and
-  lowerBound(exp) != -128
+  upperBound(exp) != 2147483647.toBigInt() and
+  upperBound(exp) != 268435455.toBigInt() and
+  upperBound(exp) != 33554431.toBigInt() and
+  upperBound(exp) != 8388607.toBigInt() and
+  upperBound(exp) != 65535.toBigInt() and
+  upperBound(exp) != 32767.toBigInt() and
+  upperBound(exp) != 255.toBigInt() and
+  upperBound(exp) != 127.toBigInt() and
+  lowerBound(exp) != "-2147483648".toBigInt() and
+  lowerBound(exp) != -268435456.toBigInt() and
+  lowerBound(exp) != -33554432.toBigInt() and
+  lowerBound(exp) != -8388608.toBigInt() and
+  lowerBound(exp) != -65536.toBigInt() and
+  lowerBound(exp) != -32768.toBigInt() and
+  lowerBound(exp) != -128.toBigInt()
   or
-  lowerBound(exp) = 0 and
-  upperBound(exp) = 1
+  lowerBound(exp) = 0.toBigInt() and
+  upperBound(exp) = 1.toBigInt()
 }
 
 /** Holds if expressions are of different size or range */
@@ -128,11 +128,15 @@ predicate isDifferentSize(Expr exp1, Expr exp2, Expr exp3) {
     isRealRange(exp2) and
     isRealRange(exp3)
   ) and
-  upperBound(exp1).maximum(upperBound(exp2)) - upperBound(exp1).minimum(upperBound(exp2)) < 16 and
-  lowerBound(exp1).maximum(lowerBound(exp2)) - lowerBound(exp1).minimum(lowerBound(exp2)) < 16 and
+  upperBound(exp1).maximum(upperBound(exp2)) - upperBound(exp1).minimum(upperBound(exp2)) <
+    16.toBigInt() and
+  lowerBound(exp1).maximum(lowerBound(exp2)) - lowerBound(exp1).minimum(lowerBound(exp2)) <
+    16.toBigInt() and
   (
-    upperBound(exp1).maximum(upperBound(exp3)) - upperBound(exp1).minimum(upperBound(exp3)) > 256 or
-    lowerBound(exp1).maximum(lowerBound(exp2)) - lowerBound(exp1).minimum(lowerBound(exp2)) > 256
+    upperBound(exp1).maximum(upperBound(exp3)) - upperBound(exp1).minimum(upperBound(exp3)) >
+      256.toBigInt() or
+    lowerBound(exp1).maximum(lowerBound(exp2)) - lowerBound(exp1).minimum(lowerBound(exp2)) >
+      256.toBigInt()
   )
 }
 
@@ -146,10 +150,10 @@ predicate isDifferentResults(
     isRealRange(exp2) and
     isRealRange(exp3)
   ) and
-  exists(int i1, int i2, int i3 |
-    i1 in [lowerBound(exp1).floor() .. upperBound(exp1).floor()] and
-    i2 in [lowerBound(exp2).floor() .. upperBound(exp2).floor()] and
-    i3 in [lowerBound(exp3).floor() .. upperBound(exp3).floor()] and
+  exists(QlBuiltins::BigInt i1, QlBuiltins::BigInt i2, QlBuiltins::BigInt i3 |
+    i1 = lowerBound(exp1) + [0 .. (upperBound(exp1) - lowerBound(exp1)).toInt()].toBigInt() and
+    i2 = lowerBound(exp2) + [0 .. (upperBound(exp2) - lowerBound(exp2)).toInt()].toBigInt() and
+    i3 = lowerBound(exp3) + [0 .. (upperBound(exp3) - lowerBound(exp3)).toInt()].toBigInt() and
     (
       op1 instanceof BitwiseOrExpr and
       op2 instanceof BitwiseAndExpr and