doc: minor updates.

[Ralf Wildenhues]

OK?  This makes all @uref's look nice in PDF output.

Thanks,
Ralf

    doc: minor updates.
    
    * doc/autoconf.texi (Generic Compiler Characteristics): Use
    second argument of @uref consistently, for nicer OpenMP link.
    (Polymorphic Variables): Restore font-lock.
    (Debugging): Add item for bashdb.

diff --git a/doc/autoconf.texi b/doc/autoconf.texi
index 1b22c26..d3774c0 100644
--- a/doc/autoconf.texi
+++ b/doc/autoconf.texi
@@ -7051,7 +7051,7 @@ Generic Compiler Characteristics
 @ovindex OPENMP_CXXFLAGS
 @ovindex OPENMP_FFLAGS
 @ovindex OPENMP_FCFLAGS
-OpenMP (@url{http://@/www.openmp.org/}) specifies extensions of C, C++,
address@hidden://@/www.openmp.org/, OpenMP} specifies extensions of C, C++,
 and Fortran that simplify optimization of shared memory parallelism,
 which is a common problem on multicore CPUs.
 
@@ -13467,6 +13467,7 @@ Polymorphic Variables
 AC_DEFUN([MY_ACTION],
 [AS_LITERAL_IF([$1],
   [echo "$$1"],
address@hidden $$
   [AS_VAR_COPY([var], [$1])
    echo "$var"],
   [eval 'echo "$'"$1"\"])])
@@ -25217,6 +25218,10 @@ Debugging
 @var{log-file}.
 
 @item
+Alternatively, you might use a shell with debugging capabilities like
address@hidden://bashdb.sourceforge.net/, bashdb}.
+
address@hidden
 When @command{configure} tests produce invalid results for your system,
 it may be necessary to override them: