AC_DEFINE_UNQUOTED with unresolved shell variables

[Roland Illig]

Dear autoconf developers,

in a software package I have found code like this:

FOO_DIR="${bindir}"
AC_SUBST(FOO_DIR)
AC_DEFINE_UNQUOTED(FOO_DIR, "$FOO_DIR",
                   [Directory where foo files are installed])

The problem with that is that the value of bindir is usually 
'${prefix}/bin', so the above code leads to the following line in config.h:

    #define FOO_DIR "${prefix}/bin"

Since the C preprocessor does not know about variable expansion, this 
reference will never be resolved, and as a result, the programs will not 
find the files.

What is the most elegant way of solving this? One way I could imagine is 
to drop the AC_DEFINE_UNQUOTED line and reintroduce the line via

    AM_CPPFLAGS = -DFOO_DIR="@FOO_DIR@"

Is that the preferred solution?

Thanks,

Roland

--
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