--- libs/msm/test/Jamfile.v2.orig	2026-04-15 14:38:58 UTC
+++ libs/msm/test/Jamfile.v2
@@ -19,7 +19,7 @@ project
     requirements
        <library>/boost/msm//boost_msm
        <include>.
-       <toolset>gcc:<cxxflags>"-ftemplate-depth-300 -g0"
+       <toolset>gcc:<cxxflags>"-ftemplate-depth-300 -g0 -std=c++20"
        <toolset>darwin:<cxxflags>"-ftemplate-depth-300 -g0"
        <toolset>intel:<cxxflags>"-g0"
        <toolset>gcc:<optimization>off