The following code is expected to print "1."
However, with -O1 or -O2 option, it prints "2."
(-O0 option yields the correct output "1.")
--------------------------------------------
Source code:
#include <stdio.h>
int main (void)
{
int test=1;
volatile int a = 1;
test += (0 == a);
test += ((test + test) <= -69);
printf("%d\n",test);
return 0;
}
--------------------------------------------
Compiler command line: "gcc -O1", "gcc -O2"
--------------------------------------------
Expected results: 1
--------------------------------------------
Observed results: 2
-------------------------------------------------------------
gcc -v output:
Reading specs from /usr/lib/gcc/i686-pc-cygwin/3.4.4/specs
Configured with:
/usr/build/package/orig/test.respin/gcc-3.4.4-3/configure
--verbose --prefix=/usr
--exec-prefix=/usr --sysconfdir=/etc --libdir=/usr/lib
--libexecdir=/usr/lib --mandir=/usr/share/man
--infodir=/usr/share/info
--enable-languages=c,ada,c++,d,f77,pascal,java,objc
--enable-nls
--without-included-gettext
--enable-version-specific-runtime-libs --without-x
--enable-libgcj --disable-java-awt
--with-system-zlib --enable-interpreter
--disable-libgcj-debug --enable-threads=posix
--enable-java-gc=boehm
--disable-win32-registry --enable-sjlj-exceptions
--enable-hash-synchronization --enable-libstdcxx-debug
Thread model: posix
gcc version 3.4.4
(cygming special, gdc 0.12, using dmd 0.125)
-------------------------------------------------------------
--
Summary: Failed constant folding and propagation in arithmetic
expression.
Product: gcc
Version: 3.4.4
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: hironobu dot awazu at gmail dot com
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38972
