[gdb/testsuite] Add boards/cc-with-index-cache.exp

We have a target board cc-with-gdb-index that uses the gdb-add-index script to
add a .gdb_index index to an exec.

There is however an alternative way of adding a .gdb_index: the index-cache.

Add a new target board cc-with-index-cache.

This is not superfluous for two reasons:
- there is functionality that gdb-add-index doesn't support, but the
  index-cache does: the index-cache can add an index to an exec with a
  .gnu_debugaltlink (note that when using the cc-with-gdb-index board this
  case is quietly ignored), and
- using the index-cache is excercised in only a few test-cases, and having
  this target board extends the test coverage to the entire test suite.  This
  is for instance relevant because the index-cache is written by a worker
  thread in the background, so we can check more thoroughly for data races
  (see PR symtab/30837).

Tested on x86_64-linux.

Shell script changes checked with shellcheck.

Approved-By: Tom Tromey <tom@tromey.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/gdb/contrib/cc-with-tweaks.sh b/gdb/contrib/cc-with-tweaks.sh
index 62d3bcf..abf22ca 100755
--- a/gdb/contrib/cc-with-tweaks.sh
+++ b/gdb/contrib/cc-with-tweaks.sh
@@ -43,6 +43,7 @@
 # -z compress using dwz
 # -m compress using dwz -m
 # -i make an index (.gdb_index)
+# -c make an index (currently .gdb_index) in a cache dir
 # -n make a dwarf5 index (.debug_names)
 # -p create .dwp files (Fission), you need to also use gcc option -gsplit-dwarf
 # -l creates separate debuginfo files linked to using .gnu_debuglink
@@ -85,6 +86,7 @@ output_file=a.out
 
 want_index=false
 index_options=""
+want_index_cache=false
 want_dwz=false
 want_multi=false
 want_dwp=false
@@ -97,6 +99,7 @@ while [ $# -gt 0 ]; do
 	-z) want_dwz=true ;;
 	-i) want_index=true ;;
 	-n) want_index=true; index_options=-dwarf-5;;
+	-c) want_index_cache=true ;;
 	-m) want_multi=true ;;
 	-p) want_dwp=true ;;
 	-l) want_gnu_debuglink=true ;;
@@ -209,6 +212,15 @@ if [ "$want_index" = true ]; then
     [ $rc != 0 ] && exit $rc
 fi
 
+if [ "$want_index_cache" = true ]; then
+    $GDB -q -batch \
+	-ex "set index-cache directory $INDEX_CACHE_DIR" \
+	-ex "set index-cache enabled on" \
+	-ex "file $output_file"
+    rc=$?
+    [ $rc != 0 ] && exit $rc
+fi
+
 if [ "$want_dwz" = true ] || [ "$want_multi" = true ]; then
     # Require dwz version with PR dwz/24468 fixed.
     dwz_version_major_required=0