help-make
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Advanced auto-dependencies clarification


From: Robert Mecklenburg
Subject: Advanced auto-dependencies clarification
Date: Thu, 5 Feb 2004 15:22:42 -0700

Paul, on your web page describing advanced auto-dependencies you
remark that one disadvantage of the "include foo.d" approach is:

  "The third problem is more serious: if you remove or rename a
  prerequisite file (say a C .h file), make will stop with a fatal
  error, complaining that the target doesn't exist:
  
    make: *** No rule to make target `bar.h', needed by `foo.P'.  Stop.
  
  This is because the .P file has a dependency on a file make can't
  find. It can't rebuild the .P file until all the prerequisites are
  there, and it won't realize it doesn't need the prerequisite until it
  rebuilds the .P file. Catch-22."

I believe this explanation assumes that the .P file (with the original
name) for the renamed/removed source is still included by make.
Correct?  I ask because just a few lines earlier the article provides
an example:

  SRCS = foo.c bar.c ...
  ...
  include $(SRCS:.c=.P)

that, I believe, does not suffer from this problem.  That is, if the
source file is renamed in or removed from SRCS, then make would not
include the file and the stop error would not occur.  Correct?

Thanks for the clarification,
-- 
Robert





reply via email to

[Prev in Thread] Current Thread [Next in Thread]