Current tcc don't understand an initialization of the empty struct
This problem was found trying to compile a linux kernel 2.4.26
which can be compiled by tcc 0.9.23
A test program:
////////////////////
// ./tcc -c test_3.c
// test_3.c:31: error: too many field init
#undef __GNUC__
#undef __GNUC_MINOR__
#define __GNUC__ 2
#define __GNUC_MINOR__ 95
typedef struct { } rwlock_t;
struct fs_struct {
int count;
rwlock_t lock;
int umask;
};
#define INIT_FS { \
1, \
RW_LOCK_UNLOCKED, \
0022, \
}
#if (__GNUC__ > 2 || __GNUC_MINOR__ > 91)
typedef struct { } rwlock_t;
#define RW_LOCK_UNLOCKED (rwlock_t) { }
#else
typedef struct { int gcc_is_buggy; } rwlock_t;
#define RW_LOCK_UNLOCKED (rwlock_t) { 0 }
#endif
static struct fs_struct init_fs = INIT_FS;
// static struct fs_struct init_fs = { { (1) }, (rwlock_t) { 0 }, 0022, };
// ^ with this all Ok
// static struct fs_struct init_fs = { { (1) }, (rwlock_t) { }, 0022, };
// ^ current tcc don't understand, but tcc 0.9.23 can
int main()
{
return 0;
}
////////////////////
A regression is detected after a patch 69fdb57edd
////////////////////
// A test for patch 69fdb57edd
// Author: grischka <grischka>
// Date: Wed Jun 17 02:09:07 2009 +0200
// unions: initzialize only one field
// struct {
// union {
// int a,b;
// };
// int c;
// } sss = { 1,2 };
// This had previously assigned 1,2 to a,b and 0 to c which is wrong.
//
// Expected: sss.a=1 sss.b=1 sss.c=2
int main()
{
struct {
union {
int a,b;
};
int c;
} sss = { 1, 2 };
printf ("sss.a=%d sss.b=%d sss.c=%d\n", sss.a, sss.b, sss.c);
return 0;
}
////////////////////
A regression was found trying to compile a linux kernel 2.4.26
which can be compiled by tcc 0.9.23
///////////////////
#include <stdio.h>
// test for a bug:
// compiler don't understand am extern array of structs
// $ tcc test_1.c
// test_1.c:8: error: unknown struct/union/enum
extern struct FILE std_files[4];
int main()
{
return 0;
}
//////////////////
tcc-current
/* enum/struct/union declaration. u is either VT_ENUM or VT_STRUCT */
static void struct_decl(CType *type, int u, int tdef)
...
if (tok != '{') {
v = tok;
next();
/* struct already defined ? return it */
if (v < TOK_IDENT)
expect("struct/union/enum name");
s = struct_find(v);
if (s) {
if (s->type.t != a)
tcc_error("invalid type");
goto do_decl;
} else if (tok >= TOK_IDENT && !tdef)
tcc_error("unknown struct/union/enum");
} else {
v = anon_sym++;
}
tcc-0.9.23 which don't have such error
/* enum/struct/union declaration. u is either VT_ENUM or VT_STRUCT */
static void struct_decl(CType *type, int u)
....
if (tok != '{') {
v = tok;
next();
/* struct already defined ? return it */
if (v < TOK_IDENT)
expect("struct/union/enum name");
s = struct_find(v);
if (s) {
if (s->type.t != a)
error("invalid type");
goto do_decl;
}
} else {
v = anon_sym++;
}
It is a strange patch because before this commit a gdb is working well
and after this commit there is exactly the same problem on Linux:
gdb refuses to know "main"
Author: grischka <grischka>
Date: Tue Feb 5 21:18:29 2013 +0100
tccelf: fix debug section relocation
With:
tcc -g hello.c
gdb a.out
b main
gdb refused to know "main" because of broken dwarf info.
in the same pass like
tcc -E one.c two.c three.c -o combined.i
This will allow to speed up a compilation process by using a commamd like
tcc -E *.c | tcc -o program.exe -xc -
It looks that multi-times initialization don't affect anything.
Only call to the free_defines(define_start) in tcc_preprocess()
is removed in assumption that free_defines(NULL) in
tcc_cleanup() will free all defines.
With this option on a defines are included into the output
(inside comments). This will allow to debug a problems like:
In file included from math.c:8:
In file included from /usr/include/math.h:43:
/usr/include/bits/nan.h:52: warning: NAN redefined
tcc -E -P
do not output a #line directive, a gcc compatible option
tcc -E -P1
don't follow a gcc preprocessor style and do output a standard
#line directive. In such case we don't lose a location info when
we going to compile a resulting file wtith a compiler not
understanding a gnu style line info.
A cpp from gcc do this.
A test case:
tcc -E tccasm.c -o tccasm.i
tcc -E tccasm.i -o tccasm.ii
After a patch the line numbers in tccasm.ii are the same
as in tccasm.i
Add a ".i" extension as alias for ".c"
GCC and file extensions:
.i C source code which should not be preprocessed.
Before a patch:
./tcc -E tccasm.c -o tccasm.i
./tcc -c tccasm.i -o tccasm.o
tccasm.i:1: error: unrecognized file type
seyko