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-rw-r--r--make.texinfo51
1 files changed, 39 insertions, 12 deletions
diff --git a/make.texinfo b/make.texinfo
index 7605994..45de763 100644
--- a/make.texinfo
+++ b/make.texinfo
@@ -6025,13 +6025,13 @@ $(call @var{variable},@var{param},@var{param},@dots{})
@end example
When @code{make} expands this function, it assigns each @var{param} to
-temporary variables @var{$(1)}, @var{$(2)}, etc. The variable
-@var{$(0)} will contain @var{variable}. There is no maximum number of
+temporary variables @code{$(1)}, @code{$(2)}, etc. The variable
+@code{$(0)} will contain @var{variable}. There is no maximum number of
parameter arguments. There is no minimum, either, but it doesn't make
sense to use @code{call} with no parameters.
Then @var{variable} is expanded as a @code{make} variable in the context
-of these temporary assignments. Thus, any reference to @var{$(1)} in
+of these temporary assignments. Thus, any reference to @code{$(1)} in
the value of @var{variable} will resolve to the first @var{param} in the
invocation of @code{call}.
@@ -6050,7 +6050,7 @@ Some examples may make this clearer.
This macro simply reverses its arguments:
@smallexample
-reverse = $2 $1
+reverse = $(2) $(1)
foo = a b
bar = $(call reverse,$(foo))
@@ -6063,7 +6063,7 @@ This one is slightly more interesting: it defines a macro to search for
the first instance of a program in @code{PATH}:
@smallexample
-pathsearch = $(firstword $(wildcard $(addsufix /$1,$(subst :, ,$(PATH)))))
+pathsearch = $(firstword $(wildcard $(addsufix /$(1),$(subst :, ,$(PATH)))))
LS := $(call pathsearch,ls)
@end smallexample
@@ -6072,12 +6072,12 @@ LS := $(call pathsearch,ls)
Now the variable LS contains @code{/bin/ls} or similar.
The @code{call} function can be nested. Each recursive invocation gets
-its own local values for @var{$(1)}, etc. that mask the values of
+its own local values for @code{$(1)}, etc. that mask the values of
higher-level @code{call}. For example, here is an implementation of a
@dfn{map} function:
@smallexample
-map = $(foreach a,$2,$(call $1,$a))
+map = $(foreach a,$(2),$(call $(1),$(a)))
@end smallexample
Now you can @var{map} a function that normally takes only one argument,
@@ -9280,8 +9280,8 @@ and concatenate the results.@*
@item $(call @var{var},@var{param},@dots{})
-Evaluate the variable @var{var} replacing any references to @var{$(1)},
-@var{$(2)} with the first, second, etc. @var{param} values.@*
+Evaluate the variable @var{var} replacing any references to @code{$(1)},
+@code{$(2)} with the first, second, etc. @var{param} values.@*
@xref{Call Function, ,The @code{call} Function}.
@end table
@@ -9444,6 +9444,7 @@ but the rule in the makefile was prefixed with the @code{-} special
character, so @code{make} ignored the error.
@item missing separator. Stop.
+@itemx missing separator (did you mean TAB instead of 8 spaces?). Stop.
This means that @code{make} could not understand much of anything about
the command line it just read. GNU @code{make} looks for various kinds
of separators (@code{:}, @code{=}, TAB characters, etc.) to help it
@@ -9453,8 +9454,10 @@ find a valid one.
One of the most common reasons for this message is that you (or perhaps
your oh-so-helpful editor, as is the case with many MS-Windows editors)
have attempted to indent your command scripts with spaces instead of a
-TAB character. Remember that every line in the command script must
-begin with a TAB character. Eight spaces do not count. @xref{Rule Syntax}.
+TAB character. In this case, @code{make} will use the second form of
+the error above. Remember that every line in the command script must
+begin with a TAB character. Eight spaces do not count. @xref{Rule
+Syntax}.
@item commands commence before first target. Stop.
@itemx missing rule before commands. Stop.
@@ -9501,7 +9504,7 @@ which already has been defined to have commands, this warning is issued
and the second set of commands will overwrite the first set.
@xref{Multiple Rules, ,Multiple Rules for One Target}.
-@item Circular @var{xxx} <- @var{yyy} prerequisite dropped.
+@item Circular @var{xxx} <- @var{yyy} dependency dropped.
This means that @code{make} detected a loop in the dependency graph:
after tracing the prerequisite @var{yyy} of target @var{xxx}, and its
prerequisites, etc., one of them depended on @var{xxx} again.
@@ -9531,6 +9534,30 @@ there are multiple patterns in the target section, and the third means
the target doesn't contain a pattern character (@code{%}). @xref{Static
Usage, ,Syntax of Static Pattern Rules}.
+@item warning: -jN forced in submake: disabling jobserver mode.
+This warning and the next are generated if @code{make} detects error
+conditions related to parallel processing on systems where
+sub-@code{make}s can communicate (@pxref{Options/Recursion,
+,Communicating Options to a Sub-@code{make}}). This warning is
+generated if a recursive invocation of a @code{make} process is forced
+to have @samp{-j@var{N}} in its argument list (where @var{N} is greater
+than one). This could happen, for example, if you set the @code{MAKE}
+environment variable to @samp{make -j2}. In this case, the
+sub-@code{make} doesn't communicate with other @code{make} processes and
+will simply pretend it has two jobs of its own.
+
+@item warning: jobserver unavailable: using -j1. Add `+' to parent make rule.
+In order for @code{make} processes to communicate, the parent will pass
+information to the child. Since this could result in problems if the
+child process isn't actually a @code{make}, the parent will only do this
+if it thinks the child is a @code{make}. The parent uses the normal
+algorithms to determine this (@pxref{MAKE Variable, ,How the @code{MAKE}
+Variable Works}). If the makefile is constructed such that the parent
+doesn't know the child is a @code{make} process, then the child will
+receive only part of the information necessary. In this case, the child
+will generate this warning message and proceed with its build in a
+sequential manner.
+
@end table
@node Complex Makefile, Concept Index, Make Errors, Top