On Tue, Jun 14, 2022 at 05:40:27PM +0200, Jan Beulich wrote: > GNU make 3.82 apparently has a quirk where exporting an undefined > variable prevents its value from subsequently being updated. This > situation can arise due to our adding of -rR to MAKEFLAGS, which takes > effect also on make simply re-invoking itself. Once these flags are in > effect, CC (in particular) is empty (undefined), and would be defined > only via Config.mk including StdGNU.mk or alike. With the quirk, CC > remains empty, yet with an empty CC the compiler minimum version check > fails, breaking the build. > > Move the exporting of the various tool stack component variables past > where they gain their (final) values. > > Signed-off-by: Jan Beulich <[email protected]> > --- > There may be further factors playing into the described quirk, as I've > also observed that simply running make as 2nd time would lead to > successful building of xen/. > > While this wasn't a problem until several weeks back, I've not been able > to identify which exact commit would have caused the breakage. Hence no > Fixes: tag.
Reviewed-by: Anthony PERARD <[email protected]> Looks like this happened before: be63d9d47f ("build: tweak variable exporting for make 3.82") So, maybe the issue is started again with 15a0578ca4 ("build: shuffle main Makefile"), which move the include of Config.mk even later. Thanks, -- Anthony PERARD
