Fix program symbols exported in dynsym section

Prior to this commit TinyCC was exporting symbols defined in programs
only when they resolve an undefined symbol of a library. However, the
expected behavior (see --export-dynamic in GNU ld manpage) is that all
symbols used by libraries and defined by a program should be exported in
dynsym section. This is because symbol resolution search first in
program and then in libraries, thus allowing program symbol to interpose
symbol defined in a library.

1 files changed, 11 insertions, 12 deletions

diff --git a/tccelf.c b/tccelf.c
index db81201..552a39f 100644
--- a/tccelf.c
+++ b/tccelf.c
@@ -1875,20 +1875,19 @@ static void bind_libs_dynsyms(TCCState *s1)
     /* now look at unresolved dynamic symbols and export
        corresponding symbol */
     for_each_elem(s1->dynsymtab_section, 1, esym, ElfW(Sym)) {
-        if (esym->st_shndx == SHN_UNDEF) {
-            name = (char *) s1->dynsymtab_section->link->data + esym->st_name;
-            sym_index = find_elf_sym(symtab_section, name);
-            if (sym_index) {
-                /* XXX: avoid adding a symbol if already present because of
-                   -rdynamic ? */
-                sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
+        name = (char *) s1->dynsymtab_section->link->data + esym->st_name;
+        sym_index = find_elf_sym(symtab_section, name);
+        if (sym_index) {
+            /* XXX: avoid adding a symbol if already present because of
+               -rdynamic ? */
+            sym = &((ElfW(Sym) *)symtab_section->data)[sym_index];
+            if (sym->st_shndx != SHN_UNDEF)
                 put_elf_sym(s1->dynsym, sym->st_value, sym->st_size,
                             sym->st_info, 0, sym->st_shndx, name);
-            } else {
-                /* weak symbols can stay undefined */
-                if (ELFW(ST_BIND)(esym->st_info) != STB_WEAK)
-                    tcc_warning("undefined dynamic symbol '%s'", name);
-            }
+        } else if (esym->st_shndx == SHN_UNDEF) {
+            /* weak symbols can stay undefined */
+            if (ELFW(ST_BIND)(esym->st_info) != STB_WEAK)
+                tcc_warning("undefined dynamic symbol '%s'", name);
         }
     }
 }