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-rw-r--r--make.texinfo23
1 files changed, 14 insertions, 9 deletions
diff --git a/make.texinfo b/make.texinfo
index 85375bb..0a70f20 100644
--- a/make.texinfo
+++ b/make.texinfo
@@ -4174,16 +4174,20 @@ it is this unexpanded text to which @code{make} appends the new text you
specify.
@example
+@group
variable = value
variable += more
+@end group
@end example
@noindent
is roughly equivalent to:
@example
+@group
temp = value
variable = $(temp) more
+@end group
@end example
@noindent
@@ -4213,15 +4217,16 @@ CFLAGS := $(CFLAGS) -pg # enable profiling
@end example
@noindent
-This is close, but not quite what we want. Using @samp{:=} redefines
-@code{CFLAGS} as a simply-expanded variable; this means @code{make} expands
-the text @w{@samp{$(CFLAGS) -pg}} before setting the variable. If
-@code{includes} is not yet defined, we get @w{@samp{ -O -pg}}, and a later
-definition of @code{includes} will have no effect. Conversely, by using
-@samp{+=} we set @code{CFLAGS} to the @emph{unexpanded} value
-@w{@samp{$(includes) -O -pg}}. Thus we preserve the reference to
-@code{includes}, so if that variable gets defined at any later point, a
-reference like @samp{$(CFLAGS)} still uses its value.
+This is pretty close, but not quite what we want. Using @samp{:=}
+redefines @code{CFLAGS} as a simply-expanded variable; this means
+@code{make} expands the text @w{@samp{$(CFLAGS) -pg}} before setting the
+variable. If @code{includes} is not yet defined, we get @w{@samp{ -O
+-pg}}, and a later definition of @code{includes} will have no effect.
+Conversely, by using @samp{+=} we set @code{CFLAGS} to the
+@emph{unexpanded} value @w{@samp{$(includes) -O -pg}}. Thus we preserve
+the reference to @code{includes}, so if that variable gets defined at
+any later point, a reference like @samp{$(CFLAGS)} still uses its
+value.
@node Override Directive, Defining, Appending, Using Variables
@section The @code{override} Directive