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| author | rillig <rillig@pkgsrc.org> | 2020-12-14 00:14:48 +0000 |
|---|---|---|
| committer | rillig <rillig@pkgsrc.org> | 2020-12-14 00:14:48 +0000 |
| commit | 98e234cab59f3d715baed4cabffdadac7904b56f (patch) | |
| tree | 1d00c950a963b22b076cd727e5139b0b673a5e10 /mk | |
| parent | a8d08ba93d341fac646129f8d2db5789a11c09f1 (diff) | |
| download | pkgsrc-98e234cab59f3d715baed4cabffdadac7904b56f.tar.gz | |
show-all: explain how to show the values of tricky variables
In most cases, the output of "bmake show-all" is reliable, but in a few
edge cases there may still be surprises.
Diffstat (limited to 'mk')
| -rw-r--r-- | mk/misc/show.mk | 27 |
1 files changed, 20 insertions, 7 deletions
diff --git a/mk/misc/show.mk b/mk/misc/show.mk index b18b7afc018..0940d5cd87e 100644 --- a/mk/misc/show.mk +++ b/mk/misc/show.mk @@ -1,4 +1,4 @@ -# $NetBSD: show.mk,v 1.26 2020/09/12 21:27:15 rillig Exp $ +# $NetBSD: show.mk,v 1.27 2020/12/14 00:14:48 rillig Exp $ # # This file contains some targets that print information gathered from # variables. They do not modify any variables. @@ -92,12 +92,25 @@ show-build-defs: .PHONY # For each of these groups, a specialized target show-all-${group} # is defined, e.g. "show-all-extract" for the "extract" group. # -# CAVEAT: Some few variable values that are shown here may be -# misleading. For example, make(1)'s := operator leaves references -# to undefined variables as-is, so they may be resolved later. So -# if you want to take a snapshot of the exact value of a variable, -# you have to use "snapshot!=printf %s ''${var:q}" instead of -# "snapshot:=${var}". +# CAVEAT: There are a few extreme edge cases in which the variable +# values that are shown here are not 100% correct. The closest you +# can get are the following: +# +# * To see the unexpanded definition of a variable while the +# Makefile or an included file is parsed, run "bmake -dcpv", +# which adds a lot of debug logging. +# * To see the unexpanded definition of a variable at the end +# of parsing the Makefile, run "bmake -V VARNAME". +# * To see the expanded value of a variable while the Makefile +# or an included file is parsed, add a line of the form +# ".info ${VARNAME}" to that makefile. +# * To see the expanded value of a variable at the end of +# parsing the Makefile, run "bmake -v VARNAME". +# +# In some cases, the actual value of a variable depends on the targets +# that are given on the command line, or whether bmake is run +# recursively, or whether a directory inside WRKSRC already exists. +# There is nothing the pkgsrc infrastructure can do about this. # # Keywords: debug show _vargroups # |