https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120407
--- Comment #3 from Jonathan Wakely <redi at gcc dot gnu.org> --- Similar code size increase is seen for a x86_64-linux target too. $ size reg-12.2 reg-12.3 text data bss dec hex filename 81893 2872 152 84917 14bb5 reg-12.2 816931 24296 7240 848467 cf253 reg-12.3 The static libs aren't significantly different: $ ls -l 12.[23]/lib64/libstdc++.a -rw-r--r--. 1 jwakely jwakely 43913706 Aug 31 2022 12.2/lib64/libstdc++.a -rw-r--r--. 1 jwakely jwakely 43733084 May 10 2023 12.3/lib64/libstdc++.a And I don't see any significant differences when running 'size' on those two archives (some objects got a little bigger, some got a little smaller).