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10823 should ignore DW_TAG_subprogram with DW_AT_declaration tags
10824 GCC7-derived CTF can double qualifiers on arrays
10825 ctfdump -c drops last type
10826 ctfdump -c goes off the rails with a missing parent
Reviewed by: Robert Mustacchi <rm@joyent.com>
Reviewed by: Jerry Jelinek <jerry.jelinek@joyent.com>
Reviewed by: Jason King <jason.king@joyent.com>
Approved by: Jerry Jelinek <jerry.jelinek@joyent.com>
@@ -26,11 +26,11 @@
* Copyright 2012 Jason King. All rights reserved.
* Use is subject to license terms.
*/
/*
- * Copyright 2019 Joyent, Inc.
+ * Copyright 2019, Joyent, Inc.
*/
/*
* CTF DWARF conversion theory.
*
@@ -1483,11 +1483,80 @@
return (ret);
ctf_dprintf("Got back id %d\n", *idp);
return (ctf_dwmap_add(cup, *idp, die, B_FALSE));
}
+/*
+ * Given "const int const_array3[11]", GCC7 at least will create a DIE tree of
+ * DW_TAG_const_type:DW_TAG_array_type:DW_Tag_const_type:<member_type>.
+ *
+ * Given C's syntax, this renders out as "const const int const_array3[11]". To
+ * get closer to round-tripping (and make the unit tests work), we'll peek for
+ * this case, and avoid adding the extraneous qualifier if we see that the
+ * underlying array referent already has the same qualifier.
+ *
+ * This is unfortunately less trivial than it could be: this issue applies to
+ * qualifier sets like "const volatile", as well as multi-dimensional arrays, so
+ * we need to descend down those.
+ *
+ * Returns CTF_ERR on error, or a boolean value otherwise.
+ */
static int
+needed_array_qualifier(ctf_cu_t *cup, int kind, ctf_id_t ref_id)
+{
+ const ctf_type_t *t;
+ ctf_arinfo_t arinfo;
+ int akind;
+
+ if (kind != CTF_K_CONST && kind != CTF_K_VOLATILE &&
+ kind != CTF_K_RESTRICT)
+ return (1);
+
+ if ((t = ctf_dyn_lookup_by_id(cup->cu_ctfp, ref_id)) == NULL)
+ return (CTF_ERR);
+
+ if (LCTF_INFO_KIND(cup->cu_ctfp, t->ctt_info) != CTF_K_ARRAY)
+ return (1);
+
+ if (ctf_dyn_array_info(cup->cu_ctfp, ref_id, &arinfo) != 0)
+ return (CTF_ERR);
+
+ ctf_id_t id = arinfo.ctr_contents;
+
+ for (;;) {
+ if ((t = ctf_dyn_lookup_by_id(cup->cu_ctfp, id)) == NULL)
+ return (CTF_ERR);
+
+ akind = LCTF_INFO_KIND(cup->cu_ctfp, t->ctt_info);
+
+ if (akind == kind)
+ break;
+
+ if (akind == CTF_K_ARRAY) {
+ if (ctf_dyn_array_info(cup->cu_ctfp,
+ id, &arinfo) != 0)
+ return (CTF_ERR);
+ id = arinfo.ctr_contents;
+ continue;
+ }
+
+ if (akind != CTF_K_CONST && akind != CTF_K_VOLATILE &&
+ akind != CTF_K_RESTRICT)
+ break;
+
+ id = t->ctt_type;
+ }
+
+ if (kind == akind) {
+ ctf_dprintf("ignoring extraneous %s qualifier for array %d\n",
+ ctf_kind_name(cup->cu_ctfp, kind), ref_id);
+ }
+
+ return (kind != akind);
+}
+
+static int
ctf_dwarf_create_reference(ctf_cu_t *cup, Dwarf_Die die, ctf_id_t *idp,
int kind, int isroot)
{
int ret;
ctf_id_t id;
@@ -1522,10 +1591,21 @@
ctf_free(name, namelen);
return (ret);
}
}
+ if ((ret = needed_array_qualifier(cup, kind, id)) <= 0) {
+ if (ret != 0) {
+ ret = (ctf_errno(cup->cu_ctfp));
+ } else {
+ *idp = id;
+ }
+
+ ctf_free(name, namelen);
+ return (ret);
+ }
+
if ((*idp = ctf_add_reftype(cup->cu_ctfp, isroot, name, id, kind)) ==
CTF_ERR) {
ctf_free(name, namelen);
return (ctf_errno(cup->cu_ctfp));
}
@@ -1819,11 +1899,11 @@
if ((ret = ctf_dwarf_tag(cup, arg, &tag)) != 0)
return (ret);
/*
- * We have to check for a varargs type decleration. This will
+ * We have to check for a varargs type declaration. This will
* happen in one of two ways. If we have a function pointer
* type, then it'll be done with a tag of type
* DW_TAG_unspecified_parameters. However, it only means we have
* a variable number of arguments, if we have more than one
* argument found so far. Otherwise, when we have a function
@@ -1904,14 +1984,15 @@
}
static int
ctf_dwarf_convert_function(ctf_cu_t *cup, Dwarf_Die die)
{
- int ret;
- char *name;
ctf_dwfunc_t *cdf;
Dwarf_Die tdie;
+ Dwarf_Bool b;
+ char *name;
+ int ret;
/*
* Functions that don't have a name are generally functions that have
* been inlined and thus most information about them has been lost. If
* we can't get a name, then instead of returning ENOENT, we silently
@@ -1921,11 +2002,29 @@
if (ret == ENOENT)
return (0);
return (ret);
}
- ctf_dprintf("beginning work on function %s\n", name);
+ ctf_dprintf("beginning work on function %s (die %llx)\n",
+ name, ctf_die_offset(die));
+
+ if ((ret = ctf_dwarf_boolean(cup, die, DW_AT_declaration, &b)) != 0) {
+ if (ret != ENOENT)
+ return (ret);
+ } else if (b != 0) {
+ /*
+ * GCC7 at least creates empty DW_AT_declarations for functions
+ * defined in headers. As they lack details on the function
+ * prototype, we need to ignore them. If we later actually
+ * see the relevant function's definition, we will see another
+ * DW_TAG_subprogram that is more complete.
+ */
+ ctf_dprintf("ignoring declaration of function %s (die %llx)\n",
+ name, ctf_die_offset(die));
+ return (0);
+ }
+
if ((cdf = ctf_alloc(sizeof (ctf_dwfunc_t))) == NULL) {
ctf_free(name, strlen(name) + 1);
return (ENOMEM);
}
bzero(cdf, sizeof (ctf_dwfunc_t));