Improve comments for symbol export and binding

master
Thomas Preud'homme 2016-11-12 23:16:04 +08:00
parent e9769a7249
commit 9e6610b0aa
1 changed files with 9 additions and 5 deletions

View File

@ -2069,16 +2069,17 @@ static void bind_exe_dynsyms(TCCState *s1)
}
}
/* Bind symbols of libraries: export non local symbols of executable that
resolve undefined symbols of shared libraries */
/* Bind symbols of libraries: export all non local symbols of executable that
are referenced by shared libraries. The reason is that the dynamic loader
search symbol first in executable and then in libraries. Therefore a
reference to a symbol already defined by a library can still be resolved by
a symbol in the executable. */
static void bind_libs_dynsyms(TCCState *s1)
{
const char *name;
int sym_index;
ElfW(Sym) *sym, *esym;
/* now look at unresolved dynamic symbols and export
corresponding symbol */
for_each_elem(s1->dynsymtab_section, 1, esym, ElfW(Sym)) {
name = (char *) s1->dynsymtab_section->link->data + esym->st_name;
sym_index = find_elf_sym(symtab_section, name);
@ -2096,7 +2097,10 @@ static void bind_libs_dynsyms(TCCState *s1)
}
}
/* Export all non local symbols (for shared libraries) */
/* Export all non local symbols. This is used by shared libraries so that the
non local symbols they define can resolve a reference in another shared
library or in the executable. Correspondingly, it allows undefined local
symbols to be resolved by other shared libraries or by the executable. */
static void export_global_syms(TCCState *s1)
{
int nb_syms, dynindex, index;