WG15 Defect Report Ref: 9945-2-123
Topic: MAKEFLAGS processing in make

This is an approved interpretation of 9945-2:1993.


Last update: 1997-05-20



	Topic:			MAKEFLAGS processing in make
	Relevant Sections:	6.2.3,,

Defect Report:
From: mark@mks.com (Mark Funkenhauser)
Date: Tue, 9 May 1995 16:52:57 -0400 (EDT)

Dear Standards Board,

    I would like to an request official, binding interpretation
    from WG15 concerning the following point in ISO/IEC
    9945-2:1993 (POSIX.2).

    Issue 1:
      From Section, lines 296-305, it says that
	  "The MAKEFLAGS variable shall be accessed from the environment
	   before the makefile is read. At this time, all of the options
	   ... not already included in 'MAKEFLAGS' shall be added to
	   the 'MAKEFLAGS' macro."

      This assignment of the 'MAKEFLAGS' macro is not referenced
      in, lines 482-490, where it describes macro assignments,
      so it is unspecified what the relationship is between this macro
      assignment and assignments from other different sources
      in terms of if/when this macro can be replaced from another source.

      Q1: what is the precedence for this macro assignment
	  with respect to precedence list lines 485-490?

     [ Note: .2b/D10.9 already contains wording changes for lines 482-490
	     but this case is not handled there either ]

    Proposed Solution for .2b:
      The 'MAKEFLAGS' macro created in this circumstance, should
      be between (1) and (2) (between line 485 and 486)
      and add to beginning of line 308 :
	 "The value of the MAKEFLAGS environment variable shall
	  not be used as the 'MAKEFLAGS' macro."
     [ Rationale: we want MAKEFLAGS macro to contain all the options from
	     the command line and from MAKEFLAGS env. variable.
	     and we don't want the env. variable overriding this new value
	     We do want to override this value if 'MAKEFLAGS' macro 
	     is defined in the makefile.
	     So, putting it before (2) is necessary to avoid problems with
	     the reversal of (2) and (3) when -e is specified,
	     and ensuring MAKEFLAGS env. variable is not turned into a macro
	     ensures that environment variables in (2) do not override. ]

    Issue 2:
      From lines 298-300
	 "At this time, all of the options (except -f and -p)
	 and command line macros not already included in 'MAKEFLAGS' shall
	 be added to the 'MAKEFLAGS' macro."

      Q2: The question is why are command line macros, and macros from
          the MAKEFLAGS environment variable, being added to the 'MAKEFLAGS'
	  macro? Was this non-historical behaviour intentional?

	a) This seems inconsistent with lines 377-379 which describes
	   the creation of the MAKEFLAGS variable containing all options
	   on the comand line except of the -f and -p options.
	   Why are command line macros not included here too? 

        b) This behaviour has never been true in any historical implementation.
	   There seems to be good reason for *not* doing this.

	   For example, given a command line of 
	       make CFLAGS="-s -g"
	   according to line 298-300, there should be a 'MAKEFLAGS' macro
	   created which is then put into the environment equivalent to this:
	       MAKEFLAGS="CFLAGS=-s -g"
	   but now when a 2nd level make gets invoked from a makefile command,
	   it will see inherit this MAKEFLAGS environment and will interpret
	   it as one 1 macro "CFLAGS=-s" and  1 option "-g".
	   Since "-g" is not a valid option, the 2nd level make will exit
	   with an error message.

	   The rationale did not give any reason for this new behaviour
	   and its not clear what advantage this provides since
	   macros are automatically included in the environment and 
	   vice versa which means 2nd level make's will automatically
	   inherit these values.

       Proposed solution for .2b:
	 Remove "and command line macros" from line 298.

    Thank you for your attention to this matter.

    Mark Funkenhauser

Interpretation response

Issue 1:
The standard does not speak to this issue, and as such no conformance
distinction can be made between alternative implementations based on this.
This is being referred to the sponsor.

Issue 2:
The text on page 669, lines 296-305, and page 571, lines 377-380 are in
conflict and as such the standard is unclear on this issue, and no 
conformance distinction can be made between alternative implementations 
based on this.  This is being referred to the sponsor.


Forwarded to Interpretations group: May 16 1995
Proposed resolution forwarded: Aug 11 1995
Finalized: Sept 12 1995