Fix another crash in the redundant-void-arg check.

[angelgarcia]

Summary

The check was assuming that a definition of a function always has a body, but a declaration that explicitly defaults or deletes a function is a definition too.

[alexfh]

Thanks for the fix! LG

clang-tidy/modernize/RedundantVoidArgCheck.cpp

if (const auto *Function = Nodes.getNodeAs<FunctionDecl>(FunctionId)) {
     processLambdaExpr(Result, Lambda);
   }
 }
 
 void RedundantVoidArgCheck::processFunctionDecl(
     const MatchFinder::MatchResult &Result, const FunctionDecl *Function) {
   SourceLocation Start = Function->getLocStart();
   if (Function->isThisDeclarationADefinition()) {
-    SourceLocation BeforeBody =
-        Function->getBody()->getLocStart().getLocWithOffset(-1);
-    removeVoidArgumentTokens(Result, SourceRange(Start, BeforeBody),
+    SourceLocation End;
+    if (Function->hasBody())
+      End = Function->getBody()->getLocStart().getLocWithOffset(-1);
+    else
+      End = Function->getLocEnd();
+    removeVoidArgumentTokens(Result, SourceRange(Start, End),
                              "function definition");
   } else {
     removeVoidArgumentTokens(Result, Function->getSourceRange(),
                              "function declaration");
   }
 }
 
 void RedundantVoidArgCheck::removeVoidArgumentTokens(

test/clang-tidy/modernize-redundant-void-arg.cpp

#define F(A, B)        \
   struct F_##A##_##B { \
     F_##A##_##B(void); \
   };                   \
   F_##A##_##B::F_##A##_##B(void)
 
 F(Foo, Bar) {
 
 }
+
+struct DefinitionWithNoBody {
+  DefinitionWithNoBody(void) = delete;
+  // CHECK-MESSAGES: :[[@LINE-1]]:24: warning: {{.*}} in function definition
+  // CHECK-FIXES: DefinitionWithNoBody() = delete;
+};