From 3d9c2b538272b553cfb83f605061382724921426 Mon Sep 17 00:00:00 2001 From: "Romain Geissler @ Amadeus" Date: Tue, 8 Oct 2024 17:28:30 +0200 Subject: [PATCH] [BUILD] Avoid buggy "should be explicitly initialized in the copy constructor" warning with gcc <= 8 (#3087) gcc <= 8, when building with -Wextra (and -Werror) wrongly raises this: /data/mwrep/res/mdw/SIOTF/internal/opentelemetry_cpp/trace/18-0-0-7/include/opentelemetry/trace/default_span.h: In copy constructor 'opentelemetry::v1::trace::DefaultSpan::DefaultSpan(const opentelemetry::v1::trace::DefaultSpan&)': /data/mwrep/res/mdw/SIOTF/internal/opentelemetry_cpp/trace/18-0-0-7/include/opentelemetry/trace/default_span.h:70:3: error: base class 'class opentelemetry::v1::trace::Span' should be explicitly initialized in the copy constructor [-Werror=extra] DefaultSpan(const DefaultSpan &spn) noexcept : span_context_(spn.GetContext()) {} ^~~~~~~~~~~ See on Compiler Explorer here: https://godbolt.org/z/ed5rv74nT I believe Jason Merrill fixed it in gcc for all gcc >= 9 with: https://gcc.gnu.org/git/?p=gcc.git;a=commitdiff;h=f3f7cefecc833b4ab652215ceb8b408c21dca225;hp=777083bb806dbe31ab97002b7d445191d3ee7a2d Workaround this by calling explicitly the empty Span constructor. --- api/include/opentelemetry/trace/default_span.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/api/include/opentelemetry/trace/default_span.h b/api/include/opentelemetry/trace/default_span.h index 7e3979501e..7ad6a3726e 100644 --- a/api/include/opentelemetry/trace/default_span.h +++ b/api/include/opentelemetry/trace/default_span.h @@ -66,8 +66,8 @@ class DefaultSpan : public Span DefaultSpan(SpanContext span_context) noexcept : span_context_(span_context) {} // movable and copiable - DefaultSpan(DefaultSpan &&spn) noexcept : span_context_(spn.GetContext()) {} - DefaultSpan(const DefaultSpan &spn) noexcept : span_context_(spn.GetContext()) {} + DefaultSpan(DefaultSpan &&spn) noexcept : Span(), span_context_(spn.GetContext()) {} + DefaultSpan(const DefaultSpan &spn) noexcept : Span(), span_context_(spn.GetContext()) {} private: SpanContext span_context_;