On 15/11/2018 09.27, Masahiro Yamada wrote: > GNU Make supports 'define' ... 'endef' directive, which can describe > a recipe that consists of multiple lines. > > endef > > This does not actually exploit the benefits of 'define' ... 'endef' > form. All shell commands must be concatenated with '; \' so that it > looks like a single command from the Makefile point of view. '@' can > only appear before the first action. > > The root cause of this misfortune is the '@set -e;' in if_changed_rule. > It is easily solvable by moving '@set -e' to the 'cmd' macro. > > The combo of $(call echo-cmd,*) $(cmd_*) in rule_cc_o_c and rule_as_o_S > were replaced with $(call cmd,*). The tailing back-slashes went away. > > Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> > --- > > define rule_cc_o_c > - $(call echo-cmd,checksrc) $(cmd_checksrc) \ > - $(call cmd_and_fixdep,cc_o_c) \ > - $(cmd_gen_ksymdeps) \ > - $(cmd_checkdoc) \ > - $(call echo-cmd,objtool) $(cmd_objtool) \ > - $(cmd_modversions_c) \ > - $(call echo-cmd,record_mcount) $(cmd_record_mcount) > + $(call cmd,checksrc) > + @$(call cmd_and_fixdep,cc_o_c) > + $(call cmd,gen_ksymdeps) > + $(call cmd,checkdoc) > + $(call cmd,objtool) > + $(call cmd,modversions_c) > + $(call cmd,record_mcount) > endef Does this mean that Make now spawns a new shell for each of these commands, and if so, what's the performance impact? Or am I just misreading things? If this does change the semantics (one shell instance versus many), I think that's worth mentioning explicitly in the changelog, regardless of whether there's no measuarable performance impact. Rasmus
