Index: clang/include/clang/Basic/DiagnosticGroups.td
===================================================================
--- clang/include/clang/Basic/DiagnosticGroups.td
+++ clang/include/clang/Basic/DiagnosticGroups.td
@@ -459,7 +459,9 @@
 def RangeLoopAnalysis : DiagGroup<"range-loop-analysis",
                                   [RangeLoopConstruct, RangeLoopBindReference]>;
 def ForLoopAnalysis : DiagGroup<"for-loop-analysis">;
-def LoopAnalysis : DiagGroup<"loop-analysis", [ForLoopAnalysis,
+def WhileLoopAnalysis : DiagGroup<"while-loop-analysis">;
+def LoopAnalysis : DiagGroup<"loop-analysis", [WhileLoopAnalysis,
+                                               ForLoopAnalysis,
                                                RangeLoopAnalysis]>;
 def MalformedWarningCheck : DiagGroup<"malformed-warning-check">;
 def Main : DiagGroup<"main">;
@@ -977,6 +979,7 @@
     DeleteNonVirtualDtor,
     Format,
     ForLoopAnalysis,
+    WhileLoopAnalysis,
     FrameAddress,
     Implicit,
     InfiniteRecursion,
Index: clang/include/clang/Basic/DiagnosticSemaKinds.td
===================================================================
--- clang/include/clang/Basic/DiagnosticSemaKinds.td
+++ clang/include/clang/Basic/DiagnosticSemaKinds.td
@@ -28,6 +28,12 @@
   InGroup<ForLoopAnalysis>, DefaultIgnore;
 def note_loop_iteration_here : Note<"%select{decremented|incremented}0 here">;
 
+// While loop analysis
+def warn_variables_not_in_while_loop_body : Warning<
+  "variable%select{s| %1|s %1 and %2|s %1, %2, and %3|s %1, %2, %3, and %4}0 "
+  "used in loop condition not modified in loop body">,
+  InGroup<WhileLoopAnalysis>, DefaultIgnore;
+
 def warn_duplicate_enum_values : Warning<
   "element %0 has been implicitly assigned %1 which another element has "
   "been assigned">, InGroup<DiagGroup<"duplicate-enum">>, DefaultIgnore;
Index: clang/lib/Sema/SemaStmt.cpp
===================================================================
--- clang/lib/Sema/SemaStmt.cpp
+++ clang/lib/Sema/SemaStmt.cpp
@@ -1673,51 +1673,6 @@
     }
 }
 
-StmtResult Sema::ActOnWhileStmt(SourceLocation WhileLoc,
-                                SourceLocation LParenLoc, ConditionResult Cond,
-                                SourceLocation RParenLoc, Stmt *Body) {
-  if (Cond.isInvalid())
-    return StmtError();
-
-  auto CondVal = Cond.get();
-  CheckBreakContinueBinding(CondVal.second);
-
-  if (CondVal.second &&
-      !Diags.isIgnored(diag::warn_comma_operator, CondVal.second->getExprLoc()))
-    CommaVisitor(*this).Visit(CondVal.second);
-
-  if (isa<NullStmt>(Body))
-    getCurCompoundScope().setHasEmptyLoopBodies();
-
-  return WhileStmt::Create(Context, CondVal.first, CondVal.second, Body,
-                           WhileLoc, LParenLoc, RParenLoc);
-}
-
-StmtResult
-Sema::ActOnDoStmt(SourceLocation DoLoc, Stmt *Body,
-                  SourceLocation WhileLoc, SourceLocation CondLParen,
-                  Expr *Cond, SourceLocation CondRParen) {
-  assert(Cond && "ActOnDoStmt(): missing expression");
-
-  CheckBreakContinueBinding(Cond);
-  ExprResult CondResult = CheckBooleanCondition(DoLoc, Cond);
-  if (CondResult.isInvalid())
-    return StmtError();
-  Cond = CondResult.get();
-
-  CondResult = ActOnFinishFullExpr(Cond, DoLoc, /*DiscardedValue*/ false);
-  if (CondResult.isInvalid())
-    return StmtError();
-  Cond = CondResult.get();
-
-  // Only call the CommaVisitor for C89 due to differences in scope flags.
-  if (Cond && !getLangOpts().C99 && !getLangOpts().CPlusPlus &&
-      !Diags.isIgnored(diag::warn_comma_operator, Cond->getExprLoc()))
-    CommaVisitor(*this).Visit(Cond);
-
-  return new (Context) DoStmt(Body, Cond, DoLoc, WhileLoc, CondRParen);
-}
-
 namespace {
   // Use SetVector since the diagnostic cares about the ordering of the Decl's.
   using DeclSetVector =
@@ -1741,7 +1696,7 @@
         Ranges(Ranges),
         Simple(true) {}
 
-    bool isSimple() { return Simple; }
+    bool isSimple() const { return Simple; }
 
     // Replaces the method in EvaluatedExprVisitor.
     void VisitMemberExpr(MemberExpr* E) {
@@ -1887,6 +1842,51 @@
 
   };  // end class DeclMatcher
 
+  void CheckWhileLoopConditionalStatement(Sema &S, Expr *Cond, Stmt *Body) {
+
+    if (S.Diags.isIgnored(diag::warn_variables_not_in_while_loop_body,
+                          Cond->getBeginLoc()))
+      return;
+
+    DeclSetVector Decls;
+    SmallVector<SourceRange, 10> Ranges;
+    DeclExtractor DE(S, Decls, Ranges);
+    DE.Visit(Cond);
+
+    // Don't analyze complex conditionals.
+    if (!DE.isSimple())
+      return;
+
+    // No decls found.
+    if (Decls.empty())
+      return;
+
+    // Don't warn on volatile, static, or global variables.
+    if (std::any_of(Decls.begin(), Decls.end(), [](const auto *VD) {
+          return VD->getType().isVolatileQualified() || VD->hasGlobalStorage();
+        }))
+      return;
+
+    if (DeclMatcher(S, Decls, Cond).FoundDeclInUse() ||
+        DeclMatcher(S, Decls, Body).FoundDeclInUse())
+      return;
+
+    auto Diag = S.Diag(Ranges.begin()->getBegin(),
+                       diag::warn_variables_not_in_while_loop_body);
+
+    // Load decl names into diagnostic.
+    if (Decls.size() > 4) {
+      Diag << 0;
+    } else {
+      Diag << (unsigned)Decls.size();
+      for (auto *VD : Decls)
+        Diag << VD->getDeclName();
+    }
+
+    for (auto Range : Ranges)
+      Diag << Range;
+  }
+
   void CheckForLoopConditionalStatement(Sema &S, Expr *Second,
                                         Expr *Third, Stmt *Body) {
     // Condition is empty
@@ -2101,6 +2101,55 @@
 
 } // end namespace
 
+StmtResult Sema::ActOnWhileStmt(SourceLocation WhileLoc,
+                                SourceLocation LParenLoc, ConditionResult Cond,
+                                SourceLocation RParenLoc, Stmt *Body) {
+  if (Cond.isInvalid())
+    return StmtError();
+
+  auto CondVal = Cond.get();
+  CheckBreakContinueBinding(CondVal.second);
+
+  if (CondVal.second &&
+      !Diags.isIgnored(diag::warn_comma_operator, CondVal.second->getExprLoc()))
+    CommaVisitor(*this).Visit(CondVal.second);
+
+  // Check only if variable is not declared inside the condition.
+  if (!CondVal.first)
+    CheckWhileLoopConditionalStatement(*this, CondVal.second, Body);
+
+  if (isa<NullStmt>(Body))
+    getCurCompoundScope().setHasEmptyLoopBodies();
+
+  return WhileStmt::Create(Context, CondVal.first, CondVal.second, Body,
+                           WhileLoc, LParenLoc, RParenLoc);
+}
+
+StmtResult Sema::ActOnDoStmt(SourceLocation DoLoc, Stmt *Body,
+                             SourceLocation WhileLoc, SourceLocation CondLParen,
+                             Expr *Cond, SourceLocation CondRParen) {
+  assert(Cond && "ActOnDoStmt(): missing expression");
+
+  CheckBreakContinueBinding(Cond);
+  ExprResult CondResult = CheckBooleanCondition(DoLoc, Cond);
+  if (CondResult.isInvalid())
+    return StmtError();
+  Cond = CondResult.get();
+
+  CondResult = ActOnFinishFullExpr(Cond, DoLoc, /*DiscardedValue*/ false);
+  if (CondResult.isInvalid())
+    return StmtError();
+  Cond = CondResult.get();
+
+  // Only call the CommaVisitor for C89 due to differences in scope flags.
+  if (Cond && !getLangOpts().C99 && !getLangOpts().CPlusPlus &&
+      !Diags.isIgnored(diag::warn_comma_operator, Cond->getExprLoc()))
+    CommaVisitor(*this).Visit(Cond);
+
+  CheckWhileLoopConditionalStatement(*this, Cond, Body);
+
+  return new (Context) DoStmt(Body, Cond, DoLoc, WhileLoc, CondRParen);
+}
 
 void Sema::CheckBreakContinueBinding(Expr *E) {
   if (!E || getLangOpts().CPlusPlus)
Index: clang/test/Index/pragma-diag-reparse.c
===================================================================
--- clang/test/Index/pragma-diag-reparse.c
+++ clang/test/Index/pragma-diag-reparse.c
@@ -12,7 +12,7 @@
 }
 
 #pragma clang diagnostic ignored "-Wmisleading-indentation"
-void foo(void) { int b=0; while (b==b); }
+void foo(void) { int b=0; while (b==b) ++b; }
 
 // RUN: env CINDEXTEST_EDITING=1 CINDEXTEST_FAILONERROR=1 c-index-test -test-load-source-reparse 5 local \
 // RUN: -I%S/Inputs \
Index: clang/test/Misc/warning-wall.c
===================================================================
--- clang/test/Misc/warning-wall.c
+++ clang/test/Misc/warning-wall.c
@@ -19,6 +19,7 @@
 CHECK-NEXT:      -Wformat-invalid-specifier
 CHECK-NEXT:      -Wformat-insufficient-args
 CHECK-NEXT:    -Wfor-loop-analysis
+CHECK-NEXT:    -Wwhile-loop-analysis
 CHECK-NEXT:    -Wframe-address
 CHECK-NEXT:    -Wimplicit
 CHECK-NEXT:      -Wimplicit-function-declaration
Index: clang/test/Preprocessor/pragma_diagnostic_sections.cpp
===================================================================
--- clang/test/Preprocessor/pragma_diagnostic_sections.cpp
+++ clang/test/Preprocessor/pragma_diagnostic_sections.cpp
@@ -2,14 +2,14 @@
 
 // rdar://8365684
 struct S {
-    void m1() { int b; while (b==b); } // expected-warning {{always evaluates to true}}
+    void m1() { int b; while (b==b) ++b; } // expected-warning {{always evaluates to true}}
 
 #pragma clang diagnostic push
 #pragma clang diagnostic ignored "-Wtautological-compare"
-    void m2() { int b; while (b==b); }
+    void m2() { int b; while (b==b) ++b; }
 #pragma clang diagnostic pop
 
-    void m3() { int b; while (b==b); } // expected-warning {{always evaluates to true}}
+    void m3() { int b; while (b==b) ++b; } // expected-warning {{always evaluates to true}}
 };
 
 //------------------------------------------------------------------------------
@@ -18,7 +18,7 @@
 #pragma clang diagnostic ignored "-Wtautological-compare"
 template <typename T>
 struct TS {
-    void m() { T b; while (b==b); }
+    void m() { T b; while (b==b) ++b; }
 };
 #pragma clang diagnostic pop
 
Index: clang/test/SemaCXX/warn-loop-analysis.cpp
===================================================================
--- clang/test/SemaCXX/warn-loop-analysis.cpp
+++ clang/test/SemaCXX/warn-loop-analysis.cpp
@@ -41,6 +41,82 @@
   for (int *i; *i; ) {}
 }
 
+void test_while1() {
+  S s;
+  int i, j;
+  while (!s.stop()) {}
+  while (s.keep_running) {}
+  while (i < 1) { ++i; }
+  while (i < 1) {} // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+  while (i < 1) { return; }
+  while (i < 1) { break; }
+  while (i < 1) { goto exit_loop; }
+  
+exit_loop:
+  while (i < 1) { by_ref(i); }
+  while (i < 1) { by_value(i); } // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+  while (i < 1) { by_pointer(&i); }
+
+  while (i < 1) {
+    while (j < 1) { ++j; }
+    ++i;
+  }
+  while (i < 1) {
+    while (j < 1) { ++i; } // expected-warning {{variable 'j' used in loop condition not modified in loop body}}
+    ++i;
+  }
+  while (i < 1) {
+    while (i < 1) { ++j; } // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+    ++i;
+  }
+
+  int *ip, *jp;
+  while (ip < jp) { ++ip; }
+  while (ip < jp) {} // expected-warning {{variables 'ip' and 'jp' used in loop condition not modified in loop body}}
+
+  // Dereferencing pointers is ignored for now.
+  while (*ip) {}
+}
+
+void test_do_while1() {
+  S s;
+  int i, j;
+  do {} while (!s.stop());
+  do {} while (s.keep_running);
+  do { ++i; } while (i < 1);
+  do {} while (i < 1); // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+  do { return; } while (i < 1);
+  do { break; } while (i < 1);
+  do { goto exit_loop; } while (i < 1);
+
+exit_loop:
+  do { by_ref(i); } while (i < 1);
+  do { by_value(i); } while (i < 1); // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+  do { by_pointer(&i); } while (i < 1);
+
+  do {
+    do { ++j; } while (j < 1);
+    ++i;
+  } while (i < 1);
+
+  do {
+    do { ++i; } while (j < 1); // expected-warning {{variable 'j' used in loop condition not modified in loop body}}
+    ++i;
+  } while (i < 1);
+
+  do {
+    do { ++j; } while (i < 1); // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+    ++i;
+  } while (i < 1);
+
+  int *ip, *jp;
+  do { ++ip; } while (ip < jp);
+  do {} while (ip < jp); // expected-warning {{variables 'ip' and 'jp' used in loop condition not modified in loop body}}
+
+  // Dereferencing pointers is ignored for now.
+  do {} while (*ip);
+}
+
 void test2() {
   int i, j, k;
   int *ptr;
@@ -107,6 +183,138 @@
   for (; i < sizeof(j); ) { ++i; }
 }
 
+void test_while2() {
+  int i, j, k;
+  int *ptr;
+
+  // Testing CastExpr
+  while (i) {} // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+  while (i) { i = 5; }
+
+  // Testing BinaryOperator
+  while (i < j) {} // expected-warning {{variables 'i' and 'j' used in loop condition not modified in loop body}}
+  while (i < j) { i = 5; }
+  while (i < j) { j = 5; }
+
+  // Testing IntegerLiteral
+  while (i < 5) {} // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+  while (i < 5) { i = 5; }
+
+  // Testing FloatingLiteral
+  while (i < 5.0) {} // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+  while (i < 5.0) { i = 5; }
+
+  // Testing CharacterLiteral
+  while (i == 'a') {} // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+  while (i == 'a') { i = 5; }
+
+  // Testing CXXBoolLiteralExpr
+  while (i == true) {} // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+  while (i == true) { i = 5; }
+
+  // Testing GNUNullExpr
+  while (ptr == __null) {} // expected-warning {{variable 'ptr' used in loop condition not modified in loop body}}
+  while (ptr == __null) { ptr = &i; }
+
+  // Testing UnaryOperator
+  while (-i > 5) {} // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+  while (-i > 5) { ++i; }
+
+  // Testing ImaginaryLiteral
+  while (i != 3i) {} // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+  while (i != 3i) { ++i; }
+
+  // Testing ConditionalOperator
+  while (i ? j : k) {} // expected-warning {{variables 'i', 'j', and 'k' used in loop condition not modified in loop body}}
+  while (i ? j : k) { ++i; }
+  while (i ? j : k) { ++j; }
+  while (i ? j : k) { ++k; }
+  while (i) { j = i ? i : i; } // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+  while (i) { j = (i = 1) ? i : i; }
+  while (i) { j = i ? i : ++i; }
+
+  // Testing BinaryConditionalOperator
+  while (i ?: j) {} // expected-warning {{variables 'i' and 'j' used in loop condition not modified in loop body}}
+  while (i ?: j) { ++i; }
+  while (i ?: j) { ++j; }
+  while (i) { j = i ?: i; }  // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+
+  // Testing ParenExpr
+  while ((i)) { }  // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+  while ((i)) { ++i; }
+
+  // Testing non-evaluated variables
+  while (i < sizeof(j)) { } // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+  while (i < sizeof(j)) { ++j; } // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+  while (i < sizeof(j)) { ++i; }
+}
+
+void test_do_while2() {
+  int i, j, k;
+  int *ptr;
+
+  // Testing CastExpr
+  do {} while (i); // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+  do { i = 5; } while (i);
+
+  // Testing BinaryOperator
+  do {} while (i < j); // expected-warning {{variables 'i' and 'j' used in loop condition not modified in loop body}}
+  do { i = 5; } while (i < j);
+  do { j = 5; } while (i < j);
+
+  // Testing IntegerLiteral
+  do {} while (i < 5); // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+  do { i = 5; } while (i < 5);
+
+  // Testing FloatingLiteral
+  do {} while (i < 5.0); // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+  do { i = 5; } while (i < 5.0);
+
+  // Testing CharacterLiteral
+  do {} while (i == 'a'); // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+  do { i = 5; } while (i == 'a');
+
+  // Testing CXXBoolLiteralExpr
+  do {} while (i == true); // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+  do  { i = 5; } while (i == true);
+
+  // Testing GNUNullExpr
+  do {} while (ptr == __null); // expected-warning {{variable 'ptr' used in loop condition not modified in loop body}}
+  do { ptr = &i; } while (ptr == __null);
+
+  // Testing UnaryOperator
+  do {} while (-i > 5); // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+  do { ++i; } while (-i > 5);
+
+  // Testing ImaginaryLiteral
+  do {} while (i != 3i); // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+  do { ++i; } while (i != 3i);
+
+  // Testing ConditionalOperator
+  do {} while (i ? j : k); // expected-warning {{variables 'i', 'j', and 'k' used in loop condition not modified in loop body}}
+  do { ++i; } while (i ? j : k);
+  do { ++j; } while (i ? j : k);
+  do { ++k; } while (i ? j : k);
+  do { j = i ? i : i; } while (i); // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+  do { j = (i = 1) ? i : i; } while (i);
+  do { j = i ? i : ++i; } while (i);
+
+  // Testing BinaryConditionalOperator
+  do {} while (i ?: j); // expected-warning {{variables 'i' and 'j' used in loop condition not modified in loop body}}
+  do { ++i; } while (i ?: j);
+  do { ++j; } while (i ?: j);
+  do { j = i ?: i; } while (i); // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+
+  // Testing ParenExpr
+  do {} while ((i)); // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+  do { ++i; } while ((i));
+
+  // Testing non-evaluated variables
+  do {} while (i < sizeof(j)); // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+  do { ++j; } while (i < sizeof(j)); // expected-warning {{variable 'i' used in loop condition not modified in loop body}}
+  do { ++i; } while (i < sizeof(j));
+}
+
 // False positive and how to silence.
 void test3() {
   int x;
@@ -119,6 +327,28 @@
   }
 }
 
+void test_while3() {
+  int x;
+  int *ptr = &x;
+  while (x < 5) { *ptr = 6; }  // expected-warning {{variable 'x' used in loop condition not modified in loop body}}
+
+  while (x < 5) {
+    *ptr = 6;
+    (void)x;
+  }
+}
+
+void test_do_while3() {
+  int x;
+  int *ptr = &x;
+  do { *ptr = 6; } while (x < 5); // expected-warning {{variable 'x' used in loop condition not modified in loop body}}
+
+  do {
+    *ptr = 6;
+    (void)x;
+  } while (x < 5);
+}
+
 // Check ordering and printing of variables.  Max variables is currently 4.
 void test4() {
   int a, b, c, d, e, f;
@@ -132,6 +362,30 @@
   for (; d + c + b + a;);  // expected-warning {{variables 'd', 'c', 'b', and 'a' used in loop condition not modified in loop body}}
 }
 
+void test_while4() {
+  int a, b, c, d, e, f;
+  while (a);  // expected-warning {{variable 'a' used in loop condition not modified in loop body}}
+  while (a + b);  // expected-warning {{variables 'a' and 'b' used in loop condition not modified in loop body}}
+  while (a + b + c);  // expected-warning {{variables 'a', 'b', and 'c' used in loop condition not modified in loop body}}
+  while (a + b + c + d);  // expected-warning {{variables 'a', 'b', 'c', and 'd' used in loop condition not modified in loop body}}
+  while (a + b + c + d + e);  // expected-warning {{variables used in loop condition not modified in loop body}}
+  while (a + b + c + d + e + f);  // expected-warning {{variables used in loop condition not modified in loop body}}
+  while (a + c + d + b);  // expected-warning {{variables 'a', 'c', 'd', and 'b' used in loop condition not modified in loop body}}
+  while (d + c + b + a);  // expected-warning {{variables 'd', 'c', 'b', and 'a' used in loop condition not modified in loop body}}
+}
+
+void test_do_while4() {
+  int a, b, c, d, e, f;
+  do {} while (a);  // expected-warning {{variable 'a' used in loop condition not modified in loop body}}
+  do {} while (a + b);  // expected-warning {{variables 'a' and 'b' used in loop condition not modified in loop body}}
+  do {} while (a + b + c);  // expected-warning {{variables 'a', 'b', and 'c' used in loop condition not modified in loop body}}
+  do {} while (a + b + c + d);  // expected-warning {{variables 'a', 'b', 'c', and 'd' used in loop condition not modified in loop body}}
+  do {} while (a + b + c + d + e);  // expected-warning {{variables used in loop condition not modified in loop body}}
+  do {} while (a + b + c + d + e + f);  // expected-warning {{variables used in loop condition not modified in loop body}}
+  do {} while (a + c + d + b);  // expected-warning {{variables 'a', 'c', 'd', and 'b' used in loop condition not modified in loop body}}
+  do {} while (d + c + b + a);  // expected-warning {{variables 'd', 'c', 'b', and 'a' used in loop condition not modified in loop body}}
+}
+
 // Ensure that the warning doesn't fail when lots of variables are used
 // in the conditional.
 void test5() {
@@ -145,6 +399,30 @@
    // expected-warning {{variable 'a' used in loop condition not modified in loop body}}
 }
 
+void test_while5() {
+  int a;
+  while (a+a+a+a+a+a+a+a+a+a); // \
+   // expected-warning {{variable 'a' used in loop condition not modified in loop body}}
+  while (a+a+a+a+a+a+a+a+a+a+a); // \
+   // expected-warning {{variable 'a' used in loop condition not modified in loop body}}
+  while (a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a);  // \
+   // expected-warning {{variable 'a' used in loop condition not modified in loop body}}
+  while (a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a);//\
+   // expected-warning {{variable 'a' used in loop condition not modified in loop body}}
+}
+
+void test_do_while5() {
+  int a;
+  do {} while (a+a+a+a+a+a+a+a+a+a); // \
+   // expected-warning {{variable 'a' used in loop condition not modified in loop body}}
+  do {} while (a+a+a+a+a+a+a+a+a+a+a); // \
+   // expected-warning {{variable 'a' used in loop condition not modified in loop body}}
+  do {} while (a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a);  // \
+   // expected-warning {{variable 'a' used in loop condition not modified in loop body}}
+  do {} while (a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a);//\
+   // expected-warning {{variable 'a' used in loop condition not modified in loop body}}
+}
+
 // Ignore global variables and static variables.
 int x6;
 void test6() {
@@ -153,6 +431,18 @@
   for (;y;);
 }
 
+void test_while6() {
+  static int y;
+  while (x6);
+  while (y);
+}
+
+void test_do_while6() {
+  static int y;
+  do {} while (x6);
+  do {} while (y);
+}
+
 void test7() {
   int i;
   for (;;i++) {  // expected-note{{incremented here}}
@@ -279,6 +569,12 @@
   for (int i = 0; int x = f(i); ++i) {}
 }
 
+void test_while9() {
+  // Don't warn when variable is defined by the loop condition.
+  int i = 0;
+  while (int x = f(i)) { ++i; }
+}
+
 // Don't warn when decomposition variables are in the loop condition.
 // TODO: BindingDecl's which make a copy should warn.
 void test10() {
@@ -299,3 +595,41 @@
   for (auto[i, j, k] = arr; i < a; ++i) { }
   for (auto[i, j, k] = arr; i < a; ++arr[0]) { }
 };
+
+void test_while10() {
+  int arr[] = {1, 2, 3};
+  auto[i, j, k] = arr;
+  while (i < j) { ++i; ++j; }
+
+  while (i) {}
+  while (i < j) {}
+  while (i < j ) { ++arr[0]; }
+
+  int a = 1, b = 2;
+  while (a < b) {}  // expected-warning{{variables 'a' and 'b' used in loop condition not modified in loop body}}
+  while (a < b ) { ++a; }
+
+  while (i < a) {}
+  while (i < a) { ++a; }
+  while (i < a) { ++i; }
+  while (i < a) { ++arr[0]; }
+};
+
+void test_do_while10() {
+  int arr[] = {1, 2, 3};
+  auto[i, j, k] = arr;
+  do { ++i; ++j; } while(i < j);
+
+  do {} while (i);
+  do  {} while (i < j);
+  do { ++arr[0]; } while (i < j );
+
+  int a = 1, b = 2;
+  do {} while (a < b);  // expected-warning{{variables 'a' and 'b' used in loop condition not modified in loop body}}
+  do { ++a; } while (a < b );
+
+  do {} while (i < a);
+  do { ++a; } while (i < a);
+  do { ++i; } while (i < a);
+  do { ++arr[0]; } while (i < a);
+};