Hash :
8493499b
Author :
Date :
2011-12-25T09:56:44
silent-rules: fallback for makes without nested vars This fixes two problems reported for Automake (Bug#9928, Bug#10237) and is in response to a bug report for building coreutils on HP NonStop OS (Bug#10234). The problem is that HP NonStop 'make' treats a line like "AM_V_CC = $(am__v_CC_$(V))" as one that expands a macro with the funny name am__v_CC_$(V instead of the desired name am__v_CC_1 or am__v_CC_0, and since the funny macro is not defined the line is equivalent to "AM_V_CC = )"; this inserts a stray ")" when $(AM_V_CC) is used, which eventually causes 'make' to fail. The basic idea is that instead of generating Makefile.in lines like "AM_V_CC = $(am__v_CC_$(V))", we generate "AM_V_CC = $(am__v_CC_@AM_V@)". We then AC_SUBST $(V) for @AM_V@ in the usual case where `make' supports nested variables, and substitute 1 (or 0) otherwise. Similarly for usages like $(am__v_CC_$(AM_DEFAULT_VERBOSITY)). With this change, make implementations that doesn't grasp nested variable expansions will still be able to run Makefiles generated using the silent-rules option. They won't allow the user to override the make verbosity at runtime through redefinition of $(V) (as in "make V=0"); but this is still an improvement over not being able to work at all. * NEWS: Document this. * automake.in (define_verbose_var): When defining the variables, use @AM_V@ rather than $(V), and use @AM_DEFAULT_V@ rather than $(AM_DEFAULT_VERBOSITY). * doc/automake.texi (Automake silent-rules Option): Explain new system. * m4/silent.m4 (AM_SILENT_RULES): Check whether `make' supports nested variables, and substitute AM_V and AM_DEFAULT_V accordingly. * tests/silent-nested-vars.test: New test. * tests/Makefile.am (TESTS): Add it.