This fixes the issue
int main() { extern char *x; }
void main1() { extern char *x; }
t2.c:5: error: incompatible types for redefinition of 'x'
(reported by Giovanni Mascellani 2019/07/16)
Example:
int a = 1;
void f(void)
{
int a = 2;
{
extern int a; // = 1 !!
....
To get this (more) correctly there is a new function to copy
syms between local to global stacks.
Also, this patch changes the meaning of VT_EXTERN back
to the simpler and IMO more useful notion of
DECLARED but not (yet) DEFINED.
and that for both variables and functions. That is, VT_EXTERN
in tcc doesn't have to do with the keyword 'extern' necessarily.
Also this patch does allow
int x[];
as alias for
extern int x[];
(as do gcc and msvc)
see testcase, when the inner array dimension of multi-dimensional
VLAs isn't given TCC was generating invalid vstack accesses.
Those are actually invalid, so just diagnose them.
see testcases. A local 'extern int i' declaration needs to
refer to the global declaration, not to a local one it might
be shadowing. Doesn't seem to happen in the wild very often as
this was broken forever.
in presence of invalid source code we can't rely on the
next token to determine if we have or haven't already parsed
an initializer element, we really have to track it in some separate
state; it's a flag, so merge it with the other two we have (size_only
and first). Also add some syntax checks for situations which
formerly lead to vstack leaks, see the added testcases.
sometimes abstract decls in parameter lists left the returned name
uninitialized potentially leading to segfaults, like in
int f(int ()) {
return 0;
}
Deal with this.
like on 'enum myenum { L = -1 } L;'. It's a bit tedious as
there are two paths (for global vs local symbols), and because
the scope and enum_val share same storage.
* -dt now with lowercase t
* test snippets now separated by real preprocessor statements
which is valid C also for other compilers
#if defined test_xxx
< test snippet x >
#elif defined test_yyy
< test snippet y >
#elif ...
#endif
* simpler implementation, behaves like -run if no 'test_...' macros
are seen, works with -E too
* for demonstration I combined some of the small tests for errors
and warnings (56..63,74) in "60_errors_and_warnings.c"
Also:
* libtcc.c:
put tcc_preprocess() and tcc_assemble() under the setjmp clause
to let them return to caller after errors. This is for -dt -E.
* tccgen.c:
- get rid of save/restore_parse_state(), macro_ptr is saved
by begin_macro anyway, now line_num too.
- use expr_eq for parsing _Generic's controlling_type
- set nocode_wanted with const_wanted. too, This is to keep
VT_JMP on vtop when parsing preprocessor expressions.
* tccpp.c: tcc -E: suppress trailing whitespace from lines with
comments (that -E removes) such as
NO_GOTPLT_ENTRY,\t /* never generate ... */
