Warning message about file has modification time in the future.

[Kong, Michelle]

Hello,

 

I started using GNU make version 3.79.1 on Linux machine and got some warning messages that I don't understand:

 

make[3]: *** Warning: File `Makefile.real' has modification time in the future (2003-03-20 10:18:18 > 2003-03-20 10:18:17)

make[3]: warning: Clock skew detected. Your build may be incomplete.

 

We have a makefile system: each directory that has source files need to be compiled has a file called Makefile, that file will list all the source files for that directory as well as all the directories that the dependencies may locate. In the process of compiling source files, a file called "Makefile.real" is generated by the makefile system for each directory. The Makefile.real lists the source files, and for each source file, Makefile.real lists all its dependencies.  We've checked the machine times for each machine that's involved here, there's not time synchronization issue for all the machines.

 

Then I tried using GNU make version 3.80 on Solaris SunOS 5.8 and got similar warning messages:

 

make[3]: Warning: File `main/obj/all_obj' has modification time 0.016 s in the future

make[3]: warning: Clock skew detected. Your build may be incomplete.

 

Here all_obj is a file generated by the makefile system for each directory in the process of compiling source files, it lists all the object files for that directory and their dependencies'  object files as well.

 

These messages are not shown each time I compile, but they do show every now and then.  And for the second type of messages, I've even seen "modification time 0.0033 s in the future".

 

I want to know why are these messages got displayed? How can I disable the display of these type of messages?  Can I set some kind of range, say, anything less than 2 second can be ignored?

 

Thank you very much for your help on this matter.

 

Michelle