[PATCH v1 3/3] perf build: Fix !HAVE_DWARF_GETLOCATIONS_SUPPORT

[Ian Rogers <irogers@google.com>]

Testing with a LIBDW_DIR showed some issues. In dwarf-aux.h if
HAVE_DWARF_GETLOCATIONS_SUPPORT isn't defined then the code uses an
undefined errno value, so add errno.h.
In Makefile.config the dwarf feature tests need the LIBDW_DIR setting
in the CFLAGS/LDFLAGS.

Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/perf/Makefile.config  | 6 ++++++
 tools/perf/util/dwarf-aux.h | 1 +
 2 files changed, 7 insertions(+)

diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config
index 4dcf7a0fd235..5e26d3a91b36 100644
--- a/tools/perf/Makefile.config
+++ b/tools/perf/Makefile.config
@@ -159,8 +159,14 @@ ifeq ($(findstring -static,${LDFLAGS}),-static)
     DWARFLIBS += -lebl
   endif
 endif
+FEATURE_CHECK_CFLAGS-dwarf := $(LIBDW_CFLAGS)
+FEATURE_CHECK_LDFLAGS-dwarf := $(LIBDW_LDFLAGS) $(DWARFLIBS)
 FEATURE_CHECK_CFLAGS-libdw-dwarf-unwind := $(LIBDW_CFLAGS)
 FEATURE_CHECK_LDFLAGS-libdw-dwarf-unwind := $(LIBDW_LDFLAGS) $(DWARFLIBS)
+FEATURE_CHECK_CFLAGS-dwarf_getlocations := $(LIBDW_CFLAGS)
+FEATURE_CHECK_LDFLAGS-dwarf_getlocations := $(LIBDW_LDFLAGS) $(DWARFLIBS)
+FEATURE_CHECK_CFLAGS-dwarf_getcfi := $(LIBDW_CFLAGS)
+FEATURE_CHECK_LDFLAGS-dwarf_getcfi := $(LIBDW_LDFLAGS) $(DWARFLIBS)
 
 # for linking with debug library, run like:
 # make DEBUG=1 LIBBABELTRACE_DIR=/opt/libbabeltrace/
diff --git a/tools/perf/util/dwarf-aux.h b/tools/perf/util/dwarf-aux.h
index 336a3a183a78..925a9bb9fb15 100644
--- a/tools/perf/util/dwarf-aux.h
+++ b/tools/perf/util/dwarf-aux.h
@@ -177,6 +177,7 @@ void die_collect_vars(Dwarf_Die *sc_die, struct die_var_type **var_types);
 void die_collect_global_vars(Dwarf_Die *cu_die, struct die_var_type **var_types);
 
 #else /*  HAVE_DWARF_GETLOCATIONS_SUPPORT */
+#include <errno.h>
 
 static inline int die_get_var_range(Dwarf_Die *sp_die __maybe_unused,
 				    Dwarf_Die *vr_die __maybe_unused,
-- 
2.46.0.792.g87dc391469-goog