# $NetBSD: dep-var.mk,v 1.1 2020/08/22 16:51:26 rillig Exp $ # # Tests for variable references in dependency declarations. # # Uh oh, this feels so strange that probably nobody uses it. But it seems to # be the only way to reach the lower half of SuffExpandChildren. # XXX: The -dv log says: # Var_Parse: ${UNDEF1} with VARE_UNDEFERR|VARE_WANTRES # but no error message is generated for this line. # The variable expression ${UNDEF1} simply expands to an empty string. all: ${UNDEF1} # Using a double dollar in order to circumvent immediate variable expansion # feels like unintended behavior. At least the manual page says nothing at # all about defined or undefined variables in dependency lines. # # At the point where the expression ${DEF2} is expanded, the variable DEF2 # is defined, so everything's fine. all: $${DEF2} # This variable is not defined at all. # XXX: The -dv log says: # Var_Parse: ${UNDEF3} with VARE_UNDEFERR|VARE_WANTRES # but no error message is generated for this line, just like for UNDEF1. # The variable expression ${UNDEF3} simply expands to an empty string. all: $${UNDEF3} UNDEF1= undef1 DEF2= def2 undef1 def2: @echo ${.TARGET}