* m4/minuso.m4 (AM_PROG_CC_C_O): Make sure AC_PROG_CC is never called after this macro. * tests/distname.test, tests/subdir5.test, tests/subdir8.test, tests/subobj.test, tests/subobj4.test, tests/subobj5.test, tests/subobj6.test: Adjust. Report from Ralf Wildenhues.