REGEX_TALLOC
regstart = REGEX_TALLOC (num_regs, const char *);
regend = REGEX_TALLOC (num_regs, const char *);
old_regstart = REGEX_TALLOC (num_regs, const char *);
old_regend = REGEX_TALLOC (num_regs, const char *);
best_regstart = REGEX_TALLOC (num_regs, const char *);
best_regend = REGEX_TALLOC (num_regs, const char *);
reg_info = REGEX_TALLOC (num_regs, register_info_type);
reg_dummy = REGEX_TALLOC (num_regs, const char *);
reg_info_dummy = REGEX_TALLOC (num_regs, register_info_type);