Here is a list of the more common errors you might see generated by
make
, and some information about what they mean and how to fix
them.
Sometimes make
errors are not fatal, especially in the presence
of a -
prefix on a recipe line, or the -k
command line
option. Errors that are fatal are prefixed with the string
***
.
Error messages are all either prefixed with the name of the program (usually ‘make’), or, if the error is found in a makefile, the name of the file and linenumber containing the problem.
In the table below, these common prefixes are left off.
make
errors at all. They mean that a
program that make
invoked as part of a recipe returned a
non-0 error code (‘Error NN’), which make
interprets
as failure, or it exited in some other abnormal fashion (with a
signal of some type). See Errors in Recipes.
If no ***
is attached to the message, then the subprocess failed
but the rule in the makefile was prefixed with the -
special
character, so make
ignored the error.
make
could not understand much of anything
about the makefile line it just read. GNU make
looks for
various separators (:
, =
, recipe prefix characters,
etc.) to indicate what kind of line it's parsing. This message means
it couldn't 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 recipe lines with spaces
instead of a tab character. In this case, make
will use the
second form of the error above. Remember that every line in the
recipe must begin with a tab character (unless you set
.RECIPEPREFIX
; see Special Variables). Eight spaces do not
count. See Rule Syntax.
make
directive (such as a variable assignment).
Recipes must always be associated with a target.
The second form is generated if the line has a semicolon as the first
non-whitespace character; make
interprets this to mean you left
out the "target: prerequisite" section of a rule. See Rule Syntax.
make
decided it needed to build a target, but
then couldn't find any instructions in the makefile on how to do that,
either explicit or implicit (including in the default rules database).
If you want that file to be built, you will need to add a rule to your
makefile describing how that target can be built. Other possible
sources of this problem are typos in the makefile (if that filename is
wrong) or a corrupted source tree (if that file is not supposed to be
built, but rather only a prerequisite).
make
couldn't find any makefiles to read in.
The latter means that some makefile was found, but it didn't contain any
default goal and none was given on the command line. GNU make
has nothing to do in these situations.
See Arguments to Specify the Makefile.
make
allows only one recipe to be specified per target
(except for double-colon rules). If you give a recipe for a target
which already has been defined to have one, this warning is issued and
the second recipe will overwrite the first. See Multiple Rules for One Target.
make
detected a loop in the dependency graph:
after tracing the prerequisite yyy of target xxx, and its
prerequisites, etc., one of them depended on xxx again.
make
variable
xxx that, when it's expanded, will refer to itself (xxx).
This is not allowed; either use simply-expanded variables (:=
) or
use the append operator (+=
). See How to Use Variables.
%
); and the
fourth means that all three parts of the static pattern rule contain
pattern characters (%
)–only the first two parts should.
See Syntax of Static Pattern Rules.
make
detects error
conditions related to parallel processing on systems where
sub-make
s can communicate (see Communicating Options to a Sub-make
). This warning is
generated if a recursive invocation of a make
process is forced
to have ‘-jN’ in its argument list (where N is greater
than one). This could happen, for example, if you set the MAKE
environment variable to ‘make -j2’. In this case, the
sub-make
doesn't communicate with other make
processes and
will simply pretend it has two jobs of its own.
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 make
, the parent will only do this
if it thinks the child is a make
. The parent uses the normal
algorithms to determine this (see How the MAKE
Variable Works). If the makefile is constructed such that the parent
doesn't know the child is a 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.