GNU make: Secondary Expansion

3.9 Secondary Expansion Previously we learned that GNU make works in two distinct phases: a read-in phase and a target-update phase (see How make Reads a Makefile). GNU Make also has the ability to enable a second expansion of the prerequisites (only) for some or all targets defined in the makefile. In order for this second expansion to occur, the special target .SECONDEXPANSION must be defined be

[ngyuki]

Makefile の .SECONDEXPANSION、右側（前提条件）で $@ とか、パターンルールの右側の関数で % とか、使える

[fenrir-naru]

makefileの黒魔術