Make the dwarf3 reader more robust and less chatty when things go wrong

Skip some stuff when seeing an unknown language, be less chatty about
parser issues.

All the issues seem to come from the multi-file, that is the shared
(supplementary or alt) file containing debuginfo shared by all the
gcc/runtime libraries.

There are a couple of issues that this patch works around:

- The multifile contains entries for the 'D' language, which has some
  constructs we don't expect.
- We don't read partial units correctly, which means we often don't know
  the language we are looking at.
- The parser is very chatty about issues it didn't expect (even if they
  are ignored, it will still output something)

It only shows up with --read-var-info=yes which some tests enable, but
which is disabled by default.

Also increate the timeout of drd/tests/pth_cleanup_handler.c because
DWARF reading is so slow.

https://bugs.kde.org/show_bug.cgi?id=433500

diff --git a/NEWS b/NEWS
index 3a34269869d0ae3157d9cfed004f7fa0b4aefb65..adcb8524864d37ccf42d8210db7de254a22d0d7a 100644 (file)
--- a/NEWS
+++ b/NEWS
@@ -118,6 +118,7 @@ where XXXXXX is the bug number as listed below.
 428648  s390_emit_load_mem panics due to 20-bit offset for vector load
 428716  cppcheck detects potential leak in VEX/useful/smchash.c
 428909  helgrind: need to intercept duplicate libc definitions for Fedora 33
+429352  PPC ISA 3.1 support is missing, part 7
 429692  unhandled ppc64le-linux syscall: 147 (getsid)
 429864  s390x: C++ atomic test_and_set yields false-positive memcheck
         diagnostics
@@ -132,8 +133,8 @@ where XXXXXX is the bug number as listed below.
 432809  VEX should support REX.W + POPF
 432861  PPC modsw and modsd give incorrect results for 1 mod 12
 432215  Add debuginfod functionality
+433500  DRD regtest faulures when libstdc++ and libgcc debuginfo are installed
 n-i-bz  helgrind: If hg_cli__realloc fails, return NULL.
-429352  PPC ISA 3.1 support is missing, part 7
 
 
 Release 3.16.1 (22 June 2020)

diff --git a/coregrind/m_debuginfo/readdwarf3.c b/coregrind/m_debuginfo/readdwarf3.c
index 60fc4024476fb70b998e5a1bd0d0939f37763657..52c27d4bb4ede51f1666ecf442d95a48919cc243 100644 (file)
--- a/coregrind/m_debuginfo/readdwarf3.c
+++ b/coregrind/m_debuginfo/readdwarf3.c
@@ -3416,6 +3416,9 @@ static void typestack_push ( const CUConst* cc,
 static Bool subrange_type_denotes_array_bounds ( const D3TypeParser* parser,
                                                  DW_TAG dtag ) {
    vg_assert(dtag == DW_TAG_subrange_type);
+   /* If we don't know the language, assume false.  */
+   if (parser->language == '?')
+      return False;
    /* For most languages, a subrange_type dtag always gives the 
       bounds of an array.
       For Ada, there are additional conditions as a subrange_type
@@ -3916,6 +3919,7 @@ static void parse_type_DIE ( /*MOD*/XArray* /* of TyEnt */ tyents,
          members must have a DW_AT_data_member_location expression
          whereas union members must not. */
       Bool parent_is_struct;
+      Bool is_artificial = False;
       VG_(memset)( &fieldE, 0, sizeof(fieldE) );
       fieldE.cuOff = posn;
       fieldE.tag   = Te_Field;
@@ -3952,7 +3956,12 @@ static void parse_type_DIE ( /*MOD*/XArray* /* of TyEnt */ tyents,
                                        (SizeT)fieldE.Te.Field.nLoc,
                                        "di.readdwarf3.ptD.member.2" );
          }
+        if (attr == DW_AT_artificial && cts.u.val == 1)
+            is_artificial = True;
       }
+      /* Skip artificial members, they might not behave as expected.  */
+      if (is_artificial)
+         goto no_location;
       /* Do we have a plausible parent? */
       if (typestack_is_empty(parser)) goto_bad_DIE;
       vg_assert(ML_(TyEnt__is_type)(&parser->qparentE[parser->sp]));
@@ -3995,6 +4004,7 @@ static void parse_type_DIE ( /*MOD*/XArray* /* of TyEnt */ tyents,
             const members in C++ code which are compile time constants
             that do no exist in the class. They're not of any interest
             to us so we ignore them. */
+        no_location:
          ML_(TyEnt__make_EMPTY)(&fieldE);
       }
    }
@@ -4132,7 +4142,8 @@ static void parse_type_DIE ( /*MOD*/XArray* /* of TyEnt */ tyents,
        || (dtag == DW_TAG_subrange_type 
            && !subrange_type_denotes_array_bounds(parser, dtag))) {
       /* subrange_type other than array bound is only for Ada. */
-      vg_assert (dtag == DW_TAG_typedef || parser->language == 'A');
+      vg_assert (dtag == DW_TAG_typedef || (parser->language == 'A'
+                                            || parser->language == '?'));
       /* We can pick up a new typedef/subrange_type any time. */
       VG_(memset)(&typeE, 0, sizeof(typeE));
       typeE.cuOff = D3_INVALID_CUOFF;
@@ -4300,7 +4311,8 @@ static UWord chase_cuOff ( Bool* changed,
    ent = ML_(TyEnts__index_by_cuOff)( ents, ents_cache, cuOff );
 
    if (!ent) {
-      VG_(printf)("chase_cuOff: no entry for 0x%05lx\n", cuOff);
+      if (VG_(clo_verbosity) > 1)
+         VG_(printf)("chase_cuOff: no entry for 0x%05lx\n", cuOff);
       *changed = False;
       return cuOff;
    }

diff --git a/coregrind/m_debuginfo/storage.c b/coregrind/m_debuginfo/storage.c
index 2a975dccc3e86ab5a5ee9517674cf0ee08e74b2c..8667d123ffbb896bd2ae24c5ec007ae10329b7ba 100644 (file)
--- a/coregrind/m_debuginfo/storage.c
+++ b/coregrind/m_debuginfo/storage.c
@@ -1299,7 +1299,7 @@ void ML_(addVar)( struct _DebugInfo* di,
       ML_(read_elf_debug_info). */
    vg_assert(di->fsm.have_rx_map && di->fsm.have_rw_map);
    if (level > 0 && ML_(find_rx_mapping)(di, aMin, aMax) == NULL) {
-      if (VG_(clo_verbosity) >= 0) {
+      if (VG_(clo_verbosity) > 1) {
          VG_(message)(Vg_DebugMsg, 
             "warning: addVar: in range %#lx .. %#lx outside "
             "all rx mapped areas (%s)\n",

diff --git a/drd/tests/pth_cleanup_handler.c b/drd/tests/pth_cleanup_handler.c
index 0fb3d073d66839e457505bcf1dcdace531c62f45..e441fa3a41c4f328884c07be291348ddd34b7a35 100644 (file)
--- a/drd/tests/pth_cleanup_handler.c
+++ b/drd/tests/pth_cleanup_handler.c
@@ -39,7 +39,7 @@ int main()
   pthread_t pt1, pt2;
 
   // Make sure the program exits in case a deadlock has been triggered.
-  alarm(20);
+  alarm(60);
 
   if (pthread_mutex_init(&s_mutex, NULL) != 0)
   {