From: Paul Eggert Date: Mon, 5 Dec 2011 22:21:44 +0000 (-0800) Subject: doc: document GNU make's \# X-Git-Tag: v2.68b~44 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a8942db4d787ec19033e143151d79c5f2dac4046;p=thirdparty%2Fautoconf.git doc: document GNU make's \# * doc/autoconf.texi (Comments in Make Macros): Also mention \# in the right hand side of a macro, as an unportable usage. --- diff --git a/ChangeLog b/ChangeLog index 68dffefe..f9f4b907 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,9 @@ +2011-12-05 Paul Eggert + + doc: document GNU make's \# + * doc/autoconf.texi (Comments in Make Macros): Also mention \# + in the right hand side of a macro, as an unportable usage. + 2011-11-11 Eric Blake doc: tweak previous commit diff --git a/doc/autoconf.texi b/doc/autoconf.texi index 0569a276..d7d2231c 100644 --- a/doc/autoconf.texi +++ b/doc/autoconf.texi @@ -20214,9 +20214,12 @@ CPPFLAGS = "-DCOMMENT_CHAR='#'" @noindent as @samp{CPPFLAGS} may be expanded to @samp{"-DCOMMENT_CHAR='}. -Luckily, most @command{make} implementations disregard this and treat -single and double quotes specially here; @pxref{Comments in Make Rules}, -for a more portable alternative. + +Most @command{make} implementations disregard this and treat single and +double quotes specially here. Also, GNU @command{make} lets you put +@samp{#} into a macro value by escaping it with a backslash, i.e., +@samp{\#}. However, neither of these usages are portable. +@xref{Comments in Make Rules}, for a portable alternative. Even without quoting involved, comments can have surprising effects, because the whitespace before them is part of the variable value: