[PATCH] doc: Add a cautionary note

[Mihir Mehta]

I ran into an issue building coreutils with the "bison++" installed,
which is provided by my GNU/Linux distribution. Since this is an issue
which is not detected by the bootstrap or configure scripts, I noted the
incompatibility for users of similar distributions.
---
README-prereq | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/README-prereq b/README-prereq
index fdf89fecd..9313a2220 100644
--- a/README-prereq
+++ b/README-prereq
@@ -13,8 +13,11 @@ I.e., the tools checked for by the bootstrap script and include:
- Tar <https://www.gnu.org/software/tar/>
- Texinfo <https://www.gnu.org/software/texinfo/>

-Note please try to install/build official packages for your system.
-If these programs are not available use the following instructions
+Note: please try to install/build official packages for your system.
+Also, if using Debian or a derived GNU/Linux distribution, please
+install the bison package, since the suggested bison++ package is
+incompatible with building coreutils. If official packages are not
+available for your system, use the following instructions
to build them and install the results into a directory that you will
then use when building this package.

[Pádraig Brady]

Post by Mihir Mehta
I ran into an issue building coreutils with the "bison++" installed,
which is provided by my GNU/Linux distribution. Since this is an issue
which is not detected by the bootstrap or configure scripts, I noted the
incompatibility for users of similar distributions.
---
README-prereq | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/README-prereq b/README-prereq
index fdf89fecd..9313a2220 100644
--- a/README-prereq
+++ b/README-prereq
- Tar <https://www.gnu.org/software/tar/>
- Texinfo <https://www.gnu.org/software/texinfo/>
-Note please try to install/build official packages for your system.
-If these programs are not available use the following instructions
+Note: please try to install/build official packages for your system.
+Also, if using Debian or a derived GNU/Linux distribution, please
+install the bison package, since the suggested bison++ package is
+incompatible with building coreutils. If official packages are not
+available for your system, use the following instructions
to build them and install the results into a directory that you will
then use when building this package.

Why was bison++ suggested?
Is there an overlap in commands used in these packages?
I.E. could the disambiguation be done in the packaging?

thanks,
Pádraig

[Mihir Mehta]

Hi Pádraig,

Post by Pádraig Brady
Why was bison++ suggested?
Is there an overlap in commands used in these packages?
I.E. could the disambiguation be done in the packaging?

The packages "bison" and "bison++" are suggested, in Debian and
derivatives, as alternatives to provide "bison" on the command-line. The
trouble I'm trying to address with this patch is that these two "bison"
executables (or scripts - I haven't checked) do not do the same thing,
and in particular the version from "bison++" screws up compilation of
the coreutils.

I'm not sure how the disambiguation could be done in the packaging.

MIhir.

[Pádraig Brady]

Post by Mihir Mehta
Hi Pádraig,

Post by Pádraig Brady
Why was bison++ suggested?
Is there an overlap in commands used in these packages?
I.E. could the disambiguation be done in the packaging?

The packages "bison" and "bison++" are suggested, in Debian and
derivatives, as alternatives to provide "bison" on the command-line. The
trouble I'm trying to address with this patch is that these two "bison"
executables (or scripts - I haven't checked) do not do the same thing,
and in particular the version from "bison++" screws up compilation of
the coreutils.
I'm not sure how the disambiguation could be done in the packaging.

It seems that both bison and bison++ provide /usr/bin/bison on your distro.
This violates some debian standards so should be fixed up in the distro.
I suggest the debian bison++ package should not provide /usr/bin/bison,
especially since it's not fully compatible.
I also note that bison++ is not available at all in Fedora.

cheers,
Pádraig.

p.s. From experience I feel it's important to fix things in the right place,
as short term workarounds tend to be long lived and compound as the
line between workaround and core functionality blurs