From 2f3b7d8eb5f3f7823556b77cdd48ff2ae51b09c4 Mon Sep 17 00:00:00 2001 From: Jim Kingdon Date: Thu, 24 Mar 1994 18:32:31 +0000 Subject: [PATCH] * valops.c (value_at, value_at_lazy): Give error if we dereference a pointer to void. * gdbtypes.h: Fix comments regarding TYPE_CODE_VOID. * stabsread.c: Use 1, not 0, for TYPE_LENGTH of void types. --- gdb/ChangeLog | 5 +++++ gdb/gdbtypes.h | 6 +++++- gdb/stabsread.c | 19 ++++++++++++------- 3 files changed, 22 insertions(+), 8 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index b7572558823..06de4db6041 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,5 +1,10 @@ Thu Mar 24 07:12:09 1994 Jim Kingdon (kingdon@lioth.cygnus.com) + * valops.c (value_at, value_at_lazy): Give error if we dereference + a pointer to void. + * gdbtypes.h: Fix comments regarding TYPE_CODE_VOID. + * stabsread.c: Use 1, not 0, for TYPE_LENGTH of void types. + * stabsread.c (patch_block_stabs): Add comment about what happens if the definition is in another compilation unit from the stab. diff --git a/gdb/gdbtypes.h b/gdb/gdbtypes.h index 90faea2b071..acd21c0dcc7 100644 --- a/gdb/gdbtypes.h +++ b/gdb/gdbtypes.h @@ -86,7 +86,11 @@ enum type_code of GDB which bogusly assume that TYPE_CODE_FLT can mean complex. */ TYPE_CODE_FLT, - /* Void type (values zero length; the length field is ignored). */ + /* Void type. The length field specifies the length (probably always + one) which is used in pointer arithmetic involving pointers to + this type, but actually dereferencing such a pointer is invalid; + a void type has no length and no actual representation in memory + or registers. A pointer to a void type is a generic pointer. */ TYPE_CODE_VOID, TYPE_CODE_SET, /* Pascal sets */ diff --git a/gdb/stabsread.c b/gdb/stabsread.c index af486ff1cbe..6c81c10ae7e 100644 --- a/gdb/stabsread.c +++ b/gdb/stabsread.c @@ -1487,7 +1487,7 @@ read_type (pp, objfile) if (typenums[0] == xtypenums[0] && typenums[1] == xtypenums[1]) /* It's being defined as itself. That means it is "void". */ - type = init_type (TYPE_CODE_VOID, 0, 0, NULL, objfile); + type = init_type (TYPE_CODE_VOID, 1, 0, NULL, objfile); else { struct type *xtype; @@ -1783,7 +1783,7 @@ rs6000_builtin_type (typenum) "unsigned long", NULL); break; case 11: - rettype = init_type (TYPE_CODE_VOID, 0, 0, "void", NULL); + rettype = init_type (TYPE_CODE_VOID, 1, 0, "void", NULL); break; case 12: /* IEEE single precision (32 bit). */ @@ -3150,10 +3150,15 @@ read_sun_builtin_type (pp, typenums, objfile) if (**pp == ';') ++(*pp); - return init_type (type_bits == 0 ? TYPE_CODE_VOID : TYPE_CODE_INT, - type_bits / TARGET_CHAR_BIT, - signed_type ? 0 : TYPE_FLAG_UNSIGNED, (char *)NULL, - objfile); + if (type_bits == 0) + return init_type (TYPE_CODE_VOID, 1, + signed_type ? 0 : TYPE_FLAG_UNSIGNED, (char *)NULL, + objfile); + else + return init_type (TYPE_CODE_INT, + type_bits / TARGET_CHAR_BIT, + signed_type ? 0 : TYPE_FLAG_UNSIGNED, (char *)NULL, + objfile); } static struct type * @@ -3371,7 +3376,7 @@ read_range_type (pp, typenums, objfile) /* A type defined as a subrange of itself, with bounds both 0, is void. */ if (self_subrange && n2 == 0 && n3 == 0) - return init_type (TYPE_CODE_VOID, 0, 0, NULL, objfile); + return init_type (TYPE_CODE_VOID, 1, 0, NULL, objfile); /* If n3 is zero and n2 is not, we want a floating type, and n2 is the width in bytes. -- 2.30.2