Auto merge of #30208 - pnkfelix:fix-issue-30063, r=alexcrichton

 When given `rustc -C codegen-units=4 --emit=obj`, reset units back to 1.

Fix #30063

Note: while this code is careful to handle the case of mutliple emit types (e.g. `--emit=asm,obj`) by reporting all the emit types that conflict with codegen units in its warnings, an invocation with multiple emit types *and* `-o PATH` will continue to ignore the requested target path (with a warning), as it already does today, since the code that checks for that is further downstream.  (Multiple emit types without `-o PATH` will "work", though it will downgrade codegen-units to 1 just like all the other cases.)

r? @alexcrichton

0 files changed, 0 insertions, 0 deletions