In file included from missing_ctor.cpp:5: ./missing_ctor.h:25:1: warning: [chromium-style] Complex class/struct needs an explicit out-of-line constructor. class MissingCtorsArentOKInHeader { ^ ./missing_ctor.h:25:1: warning: [chromium-style] Complex class/struct needs an explicit out-of-line destructor. ./missing_ctor.h:51:3: warning: [chromium-style] Complex constructor has an inlined body. ExplicitlyDefaultedInlineAlsoWarns() = default; ^ ./missing_ctor.h:53:3: warning: [chromium-style] Complex constructor has an inlined body. ExplicitlyDefaultedInlineAlsoWarns( ^ ./missing_ctor.h:52:3: warning: [chromium-style] Complex destructor has an inline body. ~ExplicitlyDefaultedInlineAlsoWarns() = default; ^ 5 warnings generated.