Re: [RFC PATCH] perf: add SLANG_INC for slang.h

[Richard Purdie <richard.purdie@linuxfoundation.org>]

On Wed, 2012-09-05 at 13:54 -0700, Arnaldo Carvalho de Melo wrote:
> Em Fri, Aug 24, 2012 at 11:10:39AM +0800, Liang Li escreveu:
> > CFLAGS was previously hard coded to contain "-I/usr/include/slang" to
> > work with hosts that have "/usr/include/slang/slang.h" as well as hosts
> > that have "/usr/include/slang.h". This path can cause compile warnings
> > like:
> > 
> > cc1: warning: '/usr/include/slang' doesn't exists.
> > 
> > or
> > 
> > cc1: warning: include location "/usr/include/slang" is unsafe for
> > cross-compilation [-Wpoison-system-directories]
> > 
> > Then in some cases warnings become errors if WERROR is enabled hence
> > build errors.
> > 
> > To fix this issue, we can use -idirafter to downgrade the priority of the
> > default hard coded path. We can also make the slang include directory
> > a variable, to allow the user to specify SLANG_INC and set their own
> > include location. And add a '=' prefix to indicate better
> > compatibility with sysroot/cross compile cases.
> 
>     CC /home/acme/git/build/perf/builtin-diff.o
> In file included from util/../ui/keysyms.h:4,
>                  from util/hist.h:142,
>                  from builtin-diff.c:11:
> util/../ui/libslang.h:12:19: error: slang.h: No such file or directory
> util/../ui/libslang.h:14:5: error: "SLANG_VERSION" is not defined
> In file included from util/../ui/keysyms.h:4,
>                  from util/hist.h:142,
>                  from util/evsel.h:10,
>                  from util/evlist.h:8,
>                  from builtin-annotate.c:20:
> util/../ui/libslang.h:12:19: error: slang.h: No such file or directory
> util/../ui/libslang.h:14:5: error: "SLANG_VERSION" is not defined
> builtin-annotate.c: In function ‘hists__find_annotations’:
> builtin-annotate.c:122: error: ‘SL_KEY_RIGHT’ undeclared (first use in
> this function)
> builtin-annotate.c:122: error: (Each undeclared identifier is reported
> only once
> builtin-annotate.c:122: error: for each function it appears in.)
> builtin-annotate.c:134: error: ‘SL_KEY_LEFT’ undeclared (first use in
> this function)
> make: *** [/home/acme/git/build/perf/builtin-annotate.o] Error 1
> make: *** Waiting for unfinished jobs....
> make: *** [/home/acme/git/build/perf/builtin-diff.o] Error 1
> make: Leaving directory `/home/git/linux/tools/perf'
> [acme@sandy linux]$ cat /etc/redhat-release 
> Red Hat Enterprise Linux Server release 6.3 (Santiago)
> [acme@sandy linux]$

Does:

SLANG_INC ?= -I=/usr/include/slang

work any better? Its hard to tell from the above error which bit of the
syntax is failing. Which gcc version is it?

Cheers,

Richard