diff --git a/std/algorithm.d b/std/algorithm.d
index 8408613c2..641def579 100644
--- a/std/algorithm.d
+++ b/std/algorithm.d
@@ -3976,12 +3976,12 @@ unittest
 @safe pure nothrow unittest
 {
     int[] a1 = [1, 2, 3];
-    assert(find              ([1, 2, 3], 2));
-    assert(find!((a,b)=>a==b)([1, 2, 3], 2));
+    assert(!find              ([1, 2, 3], 2).empty);
+    assert(!find!((a,b)=>a==b)([1, 2, 3], 2).empty);
     ubyte[] a2 = [1, 2, 3];
     ubyte   b2 = 2;
-    assert(find              ([1, 2, 3], 2));
-    assert(find!((a,b)=>a==b)([1, 2, 3], 2));
+    assert(!find              ([1, 2, 3], 2).empty);
+    assert(!find!((a,b)=>a==b)([1, 2, 3], 2).empty);
 }
 @safe pure unittest
 {
@@ -7251,7 +7251,7 @@ private:
     void AllocMatrix(size_t r, size_t c) {
         rows = r;
         cols = c;
-        if (!_matrix || _matrix.length < r || _matrix[0].length < c) {
+        if (_matrix.length < r || _matrix[0].length < c) {
             delete _matrix;
             _matrix = new CostType[][](r, c);
             InitMatrix();
@@ -7262,7 +7262,7 @@ private:
         foreach (i, row; _matrix) {
             row[0] = i * _deletionIncrement;
         }
-        if (!_matrix) return;
+        if (!_matrix.length) return;
         for (auto i = 0u; i != _matrix[0].length; ++i) {
             _matrix[0][i] = i * _insertionIncrement;
         }
diff --git a/std/array.d b/std/array.d
index d485c666a..04779a9d3 100644
--- a/std/array.d
+++ b/std/array.d
@@ -1955,7 +1955,7 @@ void replaceInPlace(T, Range)(ref T[] array, size_t from, size_t to, Range stuff
        !is(T == const T) &&
        !is(T == immutable T))
 {
-    if (overlap(array, stuff))
+    if (overlap(array, stuff).length)
     {
         // use slower/conservative method
         array = array[0 .. from] ~ stuff ~ array[to .. $];
diff --git a/std/csv.d b/std/csv.d
index 98fb7e765..45744118f 100644
--- a/std/csv.d
+++ b/std/csv.d
@@ -1165,7 +1165,7 @@ public:
     void popFront()
     {
         // Skip last of record when header is depleted.
-        if(_popCount && _popCount.empty)
+        if(_popCount.ptr && _popCount.empty)
             while(!recordEnd())
             {
                 prime(1);
diff --git a/std/exception.d b/std/exception.d
index 297092a1b..60c8e20c2 100644
--- a/std/exception.d
+++ b/std/exception.d
@@ -331,6 +331,7 @@ unittest
     --------------------
  +/
 T enforce(T)(T value, lazy const(char)[] msg = null, string file = __FILE__, size_t line = __LINE__)
+    if (is(typeof({ if (!value) {} })))
 {
     if (!value) bailOut(file, line, msg);
     return value;
@@ -344,6 +345,7 @@ T enforce(T)(T value, lazy const(char)[] msg = null, string file = __FILE__, siz
  +/
 T enforce(T, string file, size_t line = __LINE__)
     (T value, lazy const(char)[] msg = null)
+    if (is(typeof({ if (!value) {} })))
 {
     if (!value) bailOut(file, line, msg);
     return value;
@@ -357,7 +359,8 @@ T enforce(T, string file, size_t line = __LINE__)
  +/
 T enforce(T, Dg, string file = __FILE__, size_t line = __LINE__)
     (T value, scope Dg dg)
-    if (isSomeFunction!Dg && is(typeof( dg() )))
+    if (isSomeFunction!Dg && is(typeof( dg() )) &&
+        is(typeof({ if (!value) {} })))
 {
     if (!value) dg();
     return value;
diff --git a/std/format.d b/std/format.d
index 6b7feb57f..c8e7b7121 100644
--- a/std/format.d
+++ b/std/format.d
@@ -2417,7 +2417,7 @@ if (is(AssocArrayTypeOf!T) && !is(T == enum) && !hasToString!(T, Char))
             fmt.writeUpToNextSpec(w);
             formatElement(w, v, fmt);
         }
-        if (f.sep)
+        if (f.sep.length)
         {
             fmt.writeUpToNextSpec(w);
             if (++i != end)
diff --git a/std/traits.d b/std/traits.d
index 0d106fc03..5d3ec321a 100644
--- a/std/traits.d
+++ b/std/traits.d
@@ -318,7 +318,7 @@ template packageName(alias T)
         enum string parent = null;
 
     static if (T.stringof.startsWith("package "))
-        enum packageName = (parent ? parent ~ '.' : "") ~ T.stringof[8 .. $];
+        enum packageName = (parent.length ? parent ~ '.' : "") ~ T.stringof[8 .. $];
     else static if (parent)
         enum packageName = parent;
     else