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No warning on type truncation
- From: "Ankur Arora" <terminus at gmail dot com>
- To: gcc-help at gnu dot org
- Date: Mon, 4 Aug 2008 00:33:49 +0530
- Subject: No warning on type truncation
Hi,
In the following program I am truncating a value from long to int (on
a 64 bit machine):
$ cat trunc.c
int main() {
int t2;
long t1 = 0xfeed00000000;
t2 = t1;
return 0;
}
That, however doesn't result in any warnings even though -Wall and
-Wextra are enabled:
$ gcc -Wextra -Wall trunc.c
$ gcc -v
Using built-in specs.
Target: x86_64-pc-linux-gnu
Configured with:
/var/tmp/portage/sys-devel/gcc-4.1.2/work/gcc-4.1.2/configure
--prefix=/usr --bindir=/usr/x86_64-pc-linux-gnu/gcc-bin/4.1.2
--includedir=/usr/lib/gcc/x86_64-pc-linux-gnu/4.1.2/include
--datadir=/usr/share/gcc-data/x86_64-pc-linux-gnu/4.1.2
--mandir=/usr/share/gcc-data/x86_64-pc-linux-gnu/4.1.2/man
--infodir=/usr/share/gcc-data/x86_64-pc-linux-gnu/4.1.2/info
--with-gxx-include-dir=/usr/lib/gcc/x86_64-pc-linux-gnu/4.1.2/include/g++-v4
--host=x86_64-pc-linux-gnu --build=x86_64-pc-linux-gnu
--disable-altivec --enable-nls --without-included-gettext
--with-system-zlib --disable-checking --disable-werror
--enable-secureplt --enable-multilib --enable-libmudflap
--disable-libssp --disable-libgcj
--enable-languages=c,c++,d,objc,obj-c++,treelang,fortran
--enable-shared --enable-threads=posix --enable-__cxa_atexit
--enable-clocale=gnu
Thread model: posix
gcc version 4.1.2 20070214 ( (gdc 0.24, using dmd 1.020)) (Gentoo 4.1.2 p1.1)
I cannot find any relevant option in the manual which enables
truncation warnings.
What am I missing?
Thanks,
Ankur
--
667:
The neighbor of the beast.