I now realize that a less intrusive approach is available: just provide
replacement filenames.h, dwarf2.h in a separate directory and pick up those
headers for a standalone build. In replacement dwarf2.h, include system
dwarf.h, #define potentially missing enum values and provide dummy enum tags.
The downside is that GCC complains about using variables of dummy enum types
in comparisons and switch statements, necessitating -Wno-switch and
-Wno-enum-compare.
Build system dependencies are a bigger problem that is beyond "scratching my
own itch" at the moment (I have to provide a CMake build script anyhow).
The below is what I submitted to import libbacktrace in the APITrace project.
I'm not sure whether it makes sense to commit it in GCC: it's not particularly
useful without the standalone CMake build script.
Alexander
diff --git a/libbacktrace/auxincl/dwarf2.h b/libbacktrace/auxincl/dwarf2.h
new file mode 100644
index 0000000..d135d8a
--- /dev/null
+++ b/libbacktrace/auxincl/dwarf2.h
@@ -0,0 +1,52 @@
+/* dwarf2.h -- minimal GCC dwarf2.h replacement for libbacktrace
+ Contributed by Alexander Monakov, ISP RAS
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+ (1) Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+
+ (2) Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in
+ the documentation and/or other materials provided with the
+ distribution.
+
+ (3) The name of the author may not be used to
+ endorse or promote products derived from this software without
+ specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE. */
+
+#ifndef BACKTRACE_AUX_DWARF2_H
+#define BACKTRACE_AUX_DWARF2_H
+
+/* Use the system header for the bulk of the definitions. */
+#include <dwarf.h>
+
+/* Provide stub enum tags. */
+enum dwarf_attribute {_dummy_dwarf_attribute};
+enum dwarf_form {_dummy_dwarf_form};
+enum dwarf_tag {_dummy_dwarf_tag};
+
+/* Define potentially missing enum values. */
+#define DW_FORM_GNU_addr_index 0x1f01
+#define DW_FORM_GNU_str_index 0x1f02
+
+#define DW_FORM_GNU_ref_alt 0x1f20
+#define DW_FORM_GNU_strp_alt 0x1f21
+
+#define DW_LNS_extended_op 0
+
+#endif
diff --git a/libbacktrace/auxincl/filenames.h b/libbacktrace/auxincl/filenames.h
new file mode 100644
index 0000000..000dd30
--- /dev/null
+++ b/libbacktrace/auxincl/filenames.h
@@ -0,0 +1,40 @@
+/* filenames.h -- minimal GCC filenames.h replacement for libbacktrace
+ Contributed by Alexander Monakov, ISP RAS
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+ (1) Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+
+ (2) Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in
+ the documentation and/or other materials provided with the
+ distribution.
+
+ (3) The name of the author may not be used to
+ endorse or promote products derived from this software without
+ specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE. */
+
+#ifndef BACKTRACE_AUX_FILENAMES_H
+#define BACKTRACE_AUX_FILENAMES_H
+
+/* Assume POSIX paths. */
+
+#define IS_DIR_SEPARATOR(c) ((c) == '/')
+#define IS_ABSOLUTE_PATH(f) ((f)[0] == '/')
+
+#endif
