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Diffstat (limited to 'gdb/doc/stabs.texinfo')
| -rw-r--r-- | gdb/doc/stabs.texinfo | 77 |
1 files changed, 38 insertions, 39 deletions
diff --git a/gdb/doc/stabs.texinfo b/gdb/doc/stabs.texinfo index a4ea1dc9c70..e96674de67d 100644 --- a/gdb/doc/stabs.texinfo +++ b/gdb/doc/stabs.texinfo @@ -79,7 +79,7 @@ This document describes the stabs debugging format. * Symbol Descriptors:: Table of symbol descriptors * Type Descriptors:: Table of type descriptors * Expanded Reference:: Reference information by stab type -* Questions:: Questions and anomolies +* Questions:: Questions and anomalies * Stab Sections:: In some object file formats, stabs are in sections. * Symbol Types Index:: Index of symbolic stab symbol type names. @@ -246,9 +246,8 @@ A @var{type-number} is often a single number. The GNU and Sun tools additionally permit a @var{type-number} to be a pair (@var{file-number},@var{filetype-number}) (the parentheses appear in the string, and serve to distinguish the two cases). The @var{file-number} -is a number starting with 1 which is incremented for each seperate -source file in the compilation (e.g., in C, each header file gets a -different number). The @var{filetype-number} is a number starting with +is 0 for the base source file, 1 for the first included file, 2 for the +next, and so on. The @var{filetype-number} is a number starting with 1 which is incremented for each new type defined in the file. (Separating the file number and the type number permits the @code{N_BINCL} optimization to succeed more often; see @ref{Include @@ -486,7 +485,7 @@ significant data in the @code{N_EINCL} symbol. @code{N_BINCL} and If the linker detects that two source files have identical stabs between an @code{N_BINCL} and @code{N_EINCL} pair (as will generally be the case for a header file), then it only puts out the stabs once. Each -additional occurance is replaced by an @code{N_EXCL} symbol. I believe +additional occurrence is replaced by an @code{N_EXCL} symbol. I believe the GNU linker and the Sun (both SunOS4 and Solaris) linker are the only ones which supports this feature. @@ -1320,7 +1319,7 @@ of specifying builtin types do not specify everything that a debugger would need to know about the type---in some cases they merely specify enough information to distinguish the type from other types. -The traditional way to define builtin types is convolunted, so new ways +The traditional way to define builtin types is convoluted, so new ways have been invented to describe them. Sun's @code{acc} uses special builtin type descriptors (@samp{b} and @samp{R}), and IBM uses negative type numbers. GDB accepts all three ways, as of version 4.8; dbx just @@ -1328,7 +1327,7 @@ accepts the traditional builtin types and perhaps one of the other two formats. The following sections describe each of these formats. @menu -* Traditional Builtin Types:: Put on your seatbelts and prepare for kludgery +* Traditional Builtin Types:: Put on your seat belts and prepare for kludgery * Builtin Type Descriptors:: Builtin types with special type descriptors * Negative Type Numbers:: Builtin types using negative type numbers @end menu @@ -1482,7 +1481,7 @@ IEEE 64-bit (double precision) floating point format. These are for complex numbers. A comment in the GDB source describes them as Fortran @code{complex}, @code{double complex}, and @code{complex*16}, respectively, but what does that mean? (i.e., Single -precision? Double precison?). +precision? Double precision?). @item 6 (NF_LDOUBLE) Long double. This should probably only be used for Sun format @@ -1821,7 +1820,7 @@ The bound is passed by value on the stack at offset @var{offset} from the argument list. @item a @var{register-number} -The bound is pased by reference in register number +The bound is passed by reference in register number @var{register-number}. @item t @var{register-number} @@ -2014,9 +2013,9 @@ The encoding of structures in stabs can be shown with an example. The following source code declares a structure tag and defines an instance of the structure in global scope. Then a @code{typedef} equates the -structure tag with a new type. Seperate stabs are generated for the +structure tag with a new type. Separate stabs are generated for the structure tag, the structure @code{typedef}, and the structure instance. The -stabs for the tag and the @code{typedef} are emited when the definitions are +stabs for the tag and the @code{typedef} are emitted when the definitions are encountered. Since the structure elements are not initialized, the stab and code for the structure variable itself is located at the end of the program in the bss section. @@ -2056,7 +2055,7 @@ types. For these, the type following the @samp{@var{name}:} part of the element description is a simple type reference. The other two structure elements are new types. In this case there is a type definition embedded after the @samp{@var{name}:}. The type definition for the -array element looks just like a type definition for a standalone array. +array element looks just like a type definition for a stand-alone array. The @code{s_next} field is a pointer to the same kind of structure that the field is an element of. So the definition of structure type 16 contains a type definition for an element which is a pointer to type 16. @@ -2123,7 +2122,7 @@ The stab for the union tag, however, is located preceding the code for the procedure in which it is defined. The stab type is @code{N_LSYM}. This would seem to imply that the union type is file scope, like the struct type @code{s_tag}. This is not true. The contents and position of the stab -for @code{u_type} do not convey any infomation about its procedure local +for @code{u_type} do not convey any information about its procedure local scope. @c FIXME: phony line break. Can probably be fixed by using an example @@ -2402,7 +2401,7 @@ Symnum n_type n_othr n_desc n_value n_strx String * Protections:: * Method Modifiers:: * Virtual Methods:: -* Inheritence:: +* Inheritance:: * Virtual Base Classes:: * Static Members:: @end menu @@ -2528,7 +2527,7 @@ would signify a local variable. A stab describing a C++ class type is similar in format to a stab describing a C struct, with each class member shown as a field in the structure. The part of the struct format describing fields is -expanded to include extra information relevent to C++ class members. +expanded to include extra information relevant to C++ class members. In addition, if the class has multiple base classes or virtual functions the struct format outside of the field parts is also augmented. @@ -2563,7 +2562,7 @@ The name ends with a period, and any characters except the period can occur in the @var{operator-name} string. The next part of the method description represents the arguments to the -method, preceeded by a colon and ending with a semi-colon. The types of +method, preceded by a colon and ending with a semi-colon. The types of the arguments are expressed in the same way argument types are expressed in C++ name mangling. In this example an @code{int} and a @code{char} map to @samp{ic}. @@ -2655,7 +2654,7 @@ mangling. @c GDB. But gpcompare.texi doesn't seem to be in the FSF GCC. @example -.stabs "name:symbol_desriptor(global function)return_type(int)", +.stabs "name:symbol_descriptor(global function)return_type(int)", N_FUN, NIL, NIL, code_addr_of_method_start .stabs "Ameth__5baseAic:F1",36,0,0,_Ameth__5baseAic @@ -2664,8 +2663,8 @@ mangling. Here is the stab for the @code{this} pointer implicit argument. The name of the @code{this} pointer is always @code{this}. Type 19, the @code{this} pointer is defined as a pointer to type 20, @code{baseA}, -but a stab defining @code{baseA} has not yet been emited. Since the -compiler knows it will be emited shortly, here it just outputs a cross +but a stab defining @code{baseA} has not yet been emitted. Since the +compiler knows it will be emitted shortly, here it just outputs a cross reference to the undefined symbol, by prefixing the symbol name with @samp{xs}. @@ -2733,8 +2732,8 @@ never start with those things. @section Protections In the simple class definition shown above all member data and -functions were publicly accessable. The example that follows -contrasts public, protected and privately accessable fields and shows +functions were publicly accessible. The example that follows +contrasts public, protected and privately accessible fields and shows how these protections are encoded in C++ stabs. If the character following the @samp{@var{field-name}:} part of the @@ -2777,7 +2776,7 @@ The @code{prot} field has protected visibility (@samp{/1}), type char (@samp{2}) and offset and size @samp{,32,8;}. The @code{pub} field has type float (@samp{12}), and offset and size @samp{,64,32;}. -Protections for member functions are signified by one digit embeded in +Protections for member functions are signified by one digit embedded in the field part of the stab describing the method. The digit is 0 if private, 1 if protected and 2 if public. Consider the C++ class definition below: @@ -2803,7 +2802,7 @@ descriptors apply to the class name struct tag and struct type. meth_name::type_def(22)=sym_desc(method)returning(int); :args(int);protection(private)modifier(normal)virtual(no); meth_name::type_def(23)=sym_desc(method)returning(char); - :args(char);protection(protected)modifier(normal)virual(no); + :args(char);protection(protected)modifier(normal)virtual(no); meth_name::type_def(24)=sym_desc(method)returning(float); :args(float);protection(public)modifier(normal)virtual(no);;", N_LSYM,NIL,NIL,NIL @@ -2844,7 +2843,7 @@ This class is described by the following stab: meth_name(VolatileMeth)::type_def(22)=sym_desc(method) returning(char);:arg(char);protection(public)modifier(volatile)virt(no) meth_name(ConstVolMeth)::type_def(23)=sym_desc(method) - returning(float);:arg(float);protection(public)modifer(const volatile) + returning(float);:arg(float);protection(public)modifier(const volatile) virtual(no);;", @dots{} @end display @@ -2907,7 +2906,7 @@ The first number represents the vtable index of the method. This is a semi-colon. The second number is a type reference to the first base class in the -inheritence hierarchy defining the virtual member function. In this +inheritance hierarchy defining the virtual member function. In this case the class stab describes a base class so the virtual function is not overriding any other definition of the method. Therefore the reference is to the type number of the class that the stab is @@ -2919,7 +2918,7 @@ third marks the end of the struct definition. For classes containing virtual functions the very last section of the string part of the stab holds a type reference to the first base -class. This is preceeded by @samp{~%} and followed by a final semi-colon. +class. This is preceded by @samp{~%} and followed by a final semi-colon. @display .stabs "class_name(A):type_def(20)=sym_desc(struct)struct_bytes(8) @@ -2940,22 +2939,22 @@ class. This is preceeded by @samp{~%} and followed by a final semi-colon. A_virt::23=##1;:i;2A*-2147483647;20;;;~%20;",128,0,0,0 @end example -@node Inheritence -@section Inheritence +@node Inheritance +@section Inheritance Stabs describing C++ derived classes include additional sections that -describe the inheritence hierarchy of the class. A derived class stab +describe the inheritance hierarchy of the class. A derived class stab also encodes the number of base classes. For each base class it tells -if the base class is virtual or not, and if the inheritence is private +if the base class is virtual or not, and if the inheritance is private or public. It also gives the offset into the object of the portion of the object corresponding to each base class. -This additional information is embeded in the class stab following the +This additional information is embedded in the class stab following the number of bytes in the struct. First the number of base classes appears bracketed by an exclamation point and a comma. Then for each base type there repeats a series: a virtual character, a -visibilty character, a number, a comma, another number, and a +visibility character, a number, a comma, another number, and a semi-colon. The virtual character is @samp{1} if the base class is virtual and @@ -3033,11 +3032,11 @@ the derivation of this class is encoded as follows. @display .stabs "derived_class_name:symbol_descriptors(struct tag&type)= type_descriptor(struct)struct_bytes(32)!num_bases(3), - base_virtual(no)inheritence_public(no)base_offset(0), + base_virtual(no)inheritance_public(no)base_offset(0), base_class_type_ref(A); - base_virtual(yes)inheritence_public(no)base_offset(NIL), + base_virtual(yes)inheritance_public(no)base_offset(NIL), base_class_type_ref(B); - base_virtual(no)inheritence_public(yes)base_offset(64), + base_virtual(no)inheritance_public(yes)base_offset(64), base_class_type_ref(C); @dots{} @end display @@ -3055,7 +3054,7 @@ the derivation of this class is encoded as follows. A derived class object consists of a concatenation in memory of the data areas defined by each base class, starting with the leftmost and ending with the rightmost in the list of base classes. The exception to this -rule is for virtual inheritence. In the example above, class @code{D} +rule is for virtual inheritance. In the example above, class @code{D} inherits virtually from base class @code{B}. This means that an instance of a @code{D} object will not contain its own @code{B} part but merely a pointer to a @code{B} part, known as a virtual base pointer. @@ -3509,7 +3508,7 @@ Open array; see @ref{Arrays}. @item b Pascal space type (AIX); see @ref{Miscellaneous Types}. Builtin integer type (Sun); see @ref{Builtin Type Descriptors}. Const and volatile -qualfied type (OS9000). +qualified type (OS9000). @item B Volatile-qualified type; see @ref{Miscellaneous Types}. @@ -3858,11 +3857,11 @@ In GNU C stabs, there seems to be no way to differentiate tag types: structures, unions, and enums (symbol descriptor @samp{T}) and typedefs (symbol descriptor @samp{t}) defined at file scope from types defined locally to a procedure or other more local scope. They all use the @code{N_LSYM} -stab type. Types defined at procedure scope are emited after the +stab type. Types defined at procedure scope are emitted after the @code{N_RBRAC} of the preceding function and before the code of the procedure in which they are defined. This is exactly the same as types defined in the source file between the two procedure bodies. -GDB overcompensates by placing all types in block #1, the block for +GDB over-compensates by placing all types in block #1, the block for symbols of file scope. This is true for default, @samp{-ansi} and @samp{-traditional} compiler options. (Bugs gcc/1063, gdb/1066.) |