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An asymbol
has the form:
typedef struct bfd_symbol { /* A pointer to the BFD which owns the symbol. This information is necessary so that a back end can work out what additional information (invisible to the application writer) is carried with the symbol. This field is *almost* redundant, since you can use section->owner instead, except that some symbols point to the global sections bfd_{abs,com,und}_section. This could be fixed by making these globals be per-bfd (or per-target-flavor). FIXME. */ struct bfd *the_bfd; /* Use bfd_asymbol_bfd(sym) to access this field. */ /* The text of the symbol. The name is left alone, and not copied; the application may not alter it. */ const char *name; /* The value of the symbol. This really should be a union of a numeric value with a pointer, since some flags indicate that a pointer to another symbol is stored here. */ symvalue value; /* Attributes of a symbol. */ #define BSF_NO_FLAGS 0x00 /* The symbol has local scope;static
inC
. The value is the offset into the section of the data. */ #define BSF_LOCAL (1 << 0) /* The symbol has global scope; initialized data inC
. The value is the offset into the section of the data. */ #define BSF_GLOBAL (1 << 1) /* The symbol has global scope and is exported. The value is the offset into the section of the data. */ #define BSF_EXPORT BSF_GLOBAL /* No real difference. */ /* A normal C symbol would be one of:BSF_LOCAL
,BSF_COMMON
,BSF_UNDEFINED
orBSF_GLOBAL
. */ /* The symbol is a debugging record. The value has an arbitrary meaning, unless BSF_DEBUGGING_RELOC is also set. */ #define BSF_DEBUGGING (1 << 2) /* The symbol denotes a function entry point. Used in ELF, perhaps others someday. */ #define BSF_FUNCTION (1 << 3) /* Used by the linker. */ #define BSF_KEEP (1 << 5) #define BSF_KEEP_G (1 << 6) /* A weak global symbol, overridable without warnings by a regular global symbol of the same name. */ #define BSF_WEAK (1 << 7) /* This symbol was created to point to a section, e.g. ELF's STT_SECTION symbols. */ #define BSF_SECTION_SYM (1 << 8) /* The symbol used to be a common symbol, but now it is allocated. */ #define BSF_OLD_COMMON (1 << 9) /* In some files the type of a symbol sometimes alters its location in an output file - ie in coff aISFCN
symbol which is alsoC_EXT
symbol appears where it was declared and not at the end of a section. This bit is set by the target BFD part to convey this information. */ #define BSF_NOT_AT_END (1 << 10) /* Signal that the symbol is the label of constructor section. */ #define BSF_CONSTRUCTOR (1 << 11) /* Signal that the symbol is a warning symbol. The name is a warning. The name of the next symbol is the one to warn about; if a reference is made to a symbol with the same name as the next symbol, a warning is issued by the linker. */ #define BSF_WARNING (1 << 12) /* Signal that the symbol is indirect. This symbol is an indirect pointer to the symbol with the same name as the next symbol. */ #define BSF_INDIRECT (1 << 13) /* BSF_FILE marks symbols that contain a file name. This is used for ELF STT_FILE symbols. */ #define BSF_FILE (1 << 14) /* Symbol is from dynamic linking information. */ #define BSF_DYNAMIC (1 << 15) /* The symbol denotes a data object. Used in ELF, and perhaps others someday. */ #define BSF_OBJECT (1 << 16) /* This symbol is a debugging symbol. The value is the offset into the section of the data. BSF_DEBUGGING should be set as well. */ #define BSF_DEBUGGING_RELOC (1 << 17) /* This symbol is thread local. Used in ELF. */ #define BSF_THREAD_LOCAL (1 << 18) /* This symbol represents a complex relocation expression, with the expression tree serialized in the symbol name. */ #define BSF_RELC (1 << 19) /* This symbol represents a signed complex relocation expression, with the expression tree serialized in the symbol name. */ #define BSF_SRELC (1 << 20) /* This symbol was created by bfd_get_synthetic_symtab. */ #define BSF_SYNTHETIC (1 << 21) /* This symbol is an indirect code object. Unrelated to BSF_INDIRECT. The dynamic linker will compute the value of this symbol by calling the function that it points to. BSF_FUNCTION must also be also set. */ #define BSF_GNU_INDIRECT_FUNCTION (1 << 22) /* This symbol is a globally unique data object. The dynamic linker will make sure that in the entire process there is just one symbol with this name and type in use. BSF_OBJECT must also be set. */ #define BSF_GNU_UNIQUE (1 << 23) flagword flags; /* A pointer to the section to which this symbol is relative. This will always be non NULL, there are special sections for undefined and absolute symbols. */ struct bfd_section *section; /* Back end special data. */ union { void *p; bfd_vma i; } udata; } asymbol;