Re: Autoconf will (not?) detect cross-tools unprefixed

[Eric Blake]

> The original posted of this thread should be smacked for the Subject:,
> and every followup poster (including me), for not adjusting it.  :-/
> 
> * Ralf Wildenhues wrote on Tue, Sep 02, 2008 at 10:37:59PM CEST:
> > 
> > I think we should keep a warning (so that unwary users get aware that
> > they *may* be using the wrong tools), but not the current one.  Proposed
> > replacement:
> > 
> >   configure: WARNING: using cross tools not prefixed with host triplet
> 
[moving a proposed patch from autoconf-patches back to this list]

What does everyone think about applying this patch?

Should the "Specifying Names" section of the manual give an
example of how to name tools in order to avoid the warning?
Does anyone have a quick example of where using a non-prefixed
tool name leads to bugs?  Maybe the warning message should
give a link to the manual on how to avoid the warning?

From: Eric Blake <address@hidden>
Date: Tue, 2 Sep 2008 16:28:31 -0600
Subject: [PATCH] Relax tone when warning about cross-compiler names.

* lib/autoconf/programs.m4 (_AC_TOOL_WARN): Support cross-compiles
with poorly named tools; the issue has been reported too many
times in the last four years to pull support.
* doc/autoconf.texi (Specifying Names, Generic Programs): Update
documentation accordingly.
Reported by Josef Tran and others, wording suggested by Ralf
Wildenhues.

Signed-off-by: Eric Blake <address@hidden>
---
 ChangeLog                |   11 +++++++++++
 doc/autoconf.texi        |   21 ++++++++++++---------
 lib/autoconf/programs.m4 |    4 +---
 3 files changed, 24 insertions(+), 12 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index f78c40f..0c9d408 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,14 @@
+2008-09-02  Eric Blake  <address@hidden>
+
+       Relax tone when warning about cross-compiler names.
+       * lib/autoconf/programs.m4 (_AC_TOOL_WARN): Support cross-compiles
+       with poorly named tools; the issue has been reported too many
+       times in the last four years to pull support.
+       * doc/autoconf.texi (Specifying Names, Generic Programs): Update
+       documentation accordingly.
+       Reported by Josef Tran and others, wording suggested by Ralf
+       Wildenhues.
+
 2008-09-01  Eric Blake  <address@hidden>
 
        Improve AC_C_BIGENDIAN.
diff --git a/doc/autoconf.texi b/doc/autoconf.texi
index 23417b3..1a93e52 100644
--- a/doc/autoconf.texi
+++ b/doc/autoconf.texi
@@ -4034,8 +4034,9 @@ Generic Programs
 @var{path}, or otherwise to @samp{ranlib} if that program exists in
 @var{path}, or to @samp{:} if neither program exists.
 
-In the future, when cross-compiling this macro will @emph{only}
-accept program names that are prefixed with the host type.
+When cross-compiling, this macro will issue a warning if no program
+prefixed with the host type could be found, as this can lead to some
+bugs if the wrong program was selected.
 For more information, see @ref{Specifying Names, , Specifying the
 system type}.
 @end defmac
@@ -4068,8 +4069,9 @@ Generic Programs
 @var{value-if-not-found} is not specified, the value of @var{variable}
 is not changed.  Calls @code{AC_SUBST} for @var{variable}.
 
-In the future, when cross-compiling this macro will @emph{not}
-accept program names that are not prefixed with the host type.
+When cross-compiling, this macro will issue a warning if no program
+prefixed with the host type could be found, as this can lead to some
+bugs if the wrong program was selected.
 @end defmac
 
 @anchor{AC_PATH_PROG}
@@ -4145,8 +4147,9 @@ Generic Programs
 Like @code{AC_CHECK_TOOL}, but set @var{variable} to the absolute
 name of the program if it is found.
 
-In the future, when cross-compiling this macro will @emph{not}
-accept program names that are not prefixed with the host type.
+When cross-compiling, this macro will issue a warning if no program
+prefixed with the host type could be found, as this can lead to some
+bugs if the wrong program was selected.
 @end defmac
 
 
@@ -17731,9 +17734,9 @@ Specifying Names
 ./configure CC=m68k-coff-gcc
 @end example
 
-In the future, when cross-compiling Autoconf will @emph{not}
-accept tools (compilers, linkers, assemblers) whose name is not
-prefixed with the host type.  The only case when this may be
+When cross-compiling, Autoconf will warn about any
+tools (compilers, linkers, assemblers) whose name is not
+prefixed with the host type.  A typical case when this may be
 useful is when you really are not cross-compiling, but only
 building for a least-common-denominator architecture: an example
 is building for @code{i386-pc-linux-gnu} while running on an
diff --git a/lib/autoconf/programs.m4 b/lib/autoconf/programs.m4
index f2245fb..63f8a13 100644
--- a/lib/autoconf/programs.m4
+++ b/lib/autoconf/programs.m4
@@ -211,9 +211,7 @@ AU_DEFUN([AC_CHECK_TOOL_PREFIX])
 AC_DEFUN([_AC_TOOL_WARN],
 [case $cross_compiling:$ac_tool_warned in
 yes:)
-AC_MSG_WARN([In the future, Autoconf will not detect cross-tools
-whose name does not start with the host triplet.  If you think this
-configuration is useful to you, please write to address@hidden)
+AC_MSG_WARN([using cross tools not prefixed with host triplet])
 ac_tool_warned=yes ;;
 esac])
 
-- 
1.6.0