MS Visual C detected a mismatch between the declaration and the definition of set_packet_header(): it is declared with its second parameter missing the const attribute. It also detected a mismatch between the declaration and the definition of parse_opt_unknown_cb(). These problems must have been introduced very recently; I do not recall seeing them before today in any of Git for Windows' ever-green branches (i.e. master semi-automatically rebased continously onto pu, next, master and maint). You could not have seen it in git.git's own Azure Pipeline, as Git for Windows' version already has support to build with MSVC (I plan to submit this directly after v2.22.0 is out). Johannes Schindelin (2): pkt-line: fix declaration of `set_packet_header()` parse-options: adjust `parse_opt_unknown_cb()`s declared return type parse-options.h | 4 +++- pkt-line.h | 2 +- 2 files changed, 4 insertions(+), 2 deletions(-) base-commit: ab15ad1a3b4b04a29415aef8c9afa2f64fc194a2 Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-192%2Fdscho%2Ffix-set_packet_header-signature-v1 Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-192/dscho/fix-set_packet_header-signature-v1 Pull-Request: https://github.com/gitgitgadget/git/pull/192 -- gitgitgadget