tccasm: Fix local statics referenced from asms

The assembler uses the ->sym_scope member to walk up the symbols
until finding a non-automatic symbol.  Since reordering the
members of Sym the sym_scope member contains a scope even for local
statics.  Formerly the use of asm_label for statics was implicitely
clearing sym_scope, now we have to do that explicitely.

Add a testcase for that, and one I encountered when moving the
clearing of sym_scope too deep into the call chain (into put_extern_sym).
This commit is contained in:
Michael Matz 2017-07-10 22:29:28 +02:00
parent 9bea88d616
commit 2acb04f7f2
2 changed files with 36 additions and 0 deletions

View File

@ -6861,6 +6861,9 @@ static void decl_initializer_alloc(CType *type, AttributeDef *ad, int r,
sym = sym_push(v, type, r | VT_SYM, 0);
patch_storage(sym, ad, NULL);
}
/* Local statics have a scope until now (for
warnings), remove it here. */
sym->sym_scope = 0;
/* update symbol definition */
put_extern_sym(sym, sec, addr, size);
} else {
@ -7257,6 +7260,9 @@ found:
tcc_error("unsupported forward __alias__ attribute");
esym = &((ElfW(Sym) *)symtab_section->data)[alias_target->c];
tsec.sh_num = esym->st_shndx;
/* Local statics have a scope until now (for
warnings), remove it here. */
sym->sym_scope = 0;
put_extern_sym2(sym, &tsec, esym->st_value, esym->st_size, 0);
}
} else {

View File

@ -3205,6 +3205,34 @@ char * get_asm_string (void)
char * str = ((char*)bug_table) + bug_table[1];
return str;
}
/* This checks another constructs with local labels. */
extern unsigned char alld_stuff[];
asm(".data\n"
".byte 41\n"
"alld_stuff:\n"
"661:\n"
".byte 42\n"
"662:\n"
".pushsection .data.ignore\n"
".long 661b - .\n" /* This reference to 661 generates an external sym
which shouldn't somehow overwrite the offset that's
already determined for it. */
".popsection\n"
".byte 662b - 661b\n" /* So that this value is undeniably 1. */);
void asm_local_label_diff (void)
{
printf ("asm_local_label_diff: %d %d\n", alld_stuff[0], alld_stuff[1]);
}
/* This checks that static local variables are available from assembler. */
void asm_local_statics (void)
{
static int localint = 41;
asm("incl %0" : "+m" (localint));
printf ("asm_local_statics: %d\n", localint);
}
#endif
unsigned int set;
@ -3378,6 +3406,8 @@ void asm_test(void)
asm volatile(".weak override_func3\n.set override_func3, base_func");
override_func3();
printf("asmstr: %s\n", get_asm_string());
asm_local_label_diff();
asm_local_statics();
#endif
/* Check that we can also load structs of appropriate layout
into registers. */