[Tinycc-devel] global declaration behavior of TCC

[Basile STARYNKEVITCH]

Sorry, 

(I don't have my ISO99 C standard here so I might be wrong)

It seems that TCC don't handle correctly a declaration appearing
several times (because it is in an include file):

// file e1.c
#include "i.h"
int plusi(int x) { return i+x; };
// eof e1.c

// file e2.c
#include <stdio.h>
#include <stdlib.h>

#include "i.h"
int main(int argc, char**argv) {
    int y=0;
    if (argc>1) y=atoi(argv[1]);
    if (argc>2) i=atoi(argv[2]);
    printf("y=%d i=%d plusi(y)=%d\n",
           y, i, plusi(y));
    return 0;
}
// eof e2.c

// file i.h
int i;
// eof i.h


When compiling with tcc -o e e1.c e2.c  I am getting:
In file included from e2.c:6:
i.h:3: 'i' defined twice

I think this behavior might not be correct. (and I know that C and C++
differs on these matters). At least gcc don't have it

I also suggest that TCC should swallow either silently or with a
warning any -O option (even if it does not do any additional
optimisation).

The following patch achieve this:

diff -Naur tcc.c.orig tcc.c
--- tcc.c.orig  2002-10-23 23:29:59.000000000 +0200
+++ tcc.c       2002-10-23 23:31:12.000000000 +0200
@@ -7526,7 +7526,9 @@
         } else 
 #endif
         if (r[1] == 'g') {
-            do_debug = 1;
+         do_debug = 1;
+       } else if (r[1] == 'O') {
+         warning("ignoring optimisation %s\n", r);
         } else if (r[1] == 'c') {
             multiple_files = 1;
             output_type = TCC_OUTPUT_OBJ;


If it matters my plateform is Debian/Linux unstable and TCC is version
0.9.12 

regards.

-- 

Basile STARYNKEVITCH         http://starynkevitch.net/Basile/ 
email: basile<at>starynkevitch<dot>net 
alias: basile<at>tunes<dot>org 
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