diff options
Diffstat (limited to 'gdb/minsyms.c')
| -rw-r--r-- | gdb/minsyms.c | 107 |
1 files changed, 83 insertions, 24 deletions
diff --git a/gdb/minsyms.c b/gdb/minsyms.c index e8ef95e..ae4c23a 100644 --- a/gdb/minsyms.c +++ b/gdb/minsyms.c @@ -412,6 +412,8 @@ lookup_minimal_symbol_by_pc_section (CORE_ADDR pc, asection *section) if (objfile->minimal_symbol_count > 0) { + int best_zero_sized = -1; + msymbol = objfile->msymbols; lo = 0; hi = objfile->minimal_symbol_count - 1; @@ -461,34 +463,91 @@ lookup_minimal_symbol_by_pc_section (CORE_ADDR pc, asection *section) == SYMBOL_VALUE_ADDRESS (&msymbol[hi + 1]))) hi++; + /* Skip various undesirable symbols. */ + while (hi >= 0) + { + /* Skip any absolute symbols. This is apparently + what adb and dbx do, and is needed for the CM-5. + There are two known possible problems: (1) on + ELF, apparently end, edata, etc. are absolute. + Not sure ignoring them here is a big deal, but if + we want to use them, the fix would go in + elfread.c. (2) I think shared library entry + points on the NeXT are absolute. If we want + special handling for this it probably should be + triggered by a special mst_abs_or_lib or some + such. */ + + if (msymbol[hi].type == mst_abs) + { + hi--; + continue; + } + + /* If SECTION was specified, skip any symbol from + wrong section. */ + if (section + /* Some types of debug info, such as COFF, + don't fill the bfd_section member, so don't + throw away symbols on those platforms. */ + && SYMBOL_BFD_SECTION (&msymbol[hi]) != NULL + && SYMBOL_BFD_SECTION (&msymbol[hi]) != section) + { + hi--; + continue; + } + + /* If the minimal symbol has a zero size, save it + but keep scanning backwards looking for one with + a non-zero size. A zero size may mean that the + symbol isn't an object or function (e.g. a + label), or it may just mean that the size was not + specified. */ + if (MSYMBOL_SIZE (&msymbol[hi]) == 0 + && best_zero_sized == -1) + { + best_zero_sized = hi; + hi--; + continue; + } + + /* Otherwise, this symbol must be as good as we're going + to get. */ + break; + } + + /* If HI has a zero size, and best_zero_sized is set, + then we had two or more zero-sized symbols; prefer + the first one we found (which may have a higher + address). Also, if we ran off the end, be sure + to back up. */ + if (best_zero_sized != -1 + && (hi < 0 || MSYMBOL_SIZE (&msymbol[hi]) == 0)) + hi = best_zero_sized; + + /* If the minimal symbol has a non-zero size, and this + PC appears to be outside the symbol's contents, then + refuse to use this symbol. If we found a zero-sized + symbol with an address greater than this symbol's, + use that instead. We assume that if symbols have + specified sizes, they do not overlap. */ + + if (hi >= 0 + && MSYMBOL_SIZE (&msymbol[hi]) != 0 + && pc >= (SYMBOL_VALUE_ADDRESS (&msymbol[hi]) + + MSYMBOL_SIZE (&msymbol[hi]))) + { + if (best_zero_sized != -1) + hi = best_zero_sized; + else + /* Go on to the next object file. */ + continue; + } + /* The minimal symbol indexed by hi now is the best one in this objfile's minimal symbol table. See if it is the best one overall. */ - /* Skip any absolute symbols. This is apparently what adb - and dbx do, and is needed for the CM-5. There are two - known possible problems: (1) on ELF, apparently end, edata, - etc. are absolute. Not sure ignoring them here is a big - deal, but if we want to use them, the fix would go in - elfread.c. (2) I think shared library entry points on the - NeXT are absolute. If we want special handling for this - it probably should be triggered by a special - mst_abs_or_lib or some such. */ - while (hi >= 0 - && msymbol[hi].type == mst_abs) - --hi; - - /* If "section" specified, skip any symbol from wrong section */ - /* This is the new code that distinguishes it from the old function */ - if (section) - while (hi >= 0 - /* Some types of debug info, such as COFF, - don't fill the bfd_section member, so don't - throw away symbols on those platforms. */ - && SYMBOL_BFD_SECTION (&msymbol[hi]) != NULL - && SYMBOL_BFD_SECTION (&msymbol[hi]) != section) - --hi; - if (hi >= 0 && ((best_symbol == NULL) || (SYMBOL_VALUE_ADDRESS (best_symbol) < |