builtins-20.c had:
if (cos((y*=2, -fabs(tan(x/-y)))) != cos((y*=2,tan(x/y))))
link_error ();
which is undefined behaviour. The test expected that y had the same
value in x/y and x/-y, but gimplification actually implements the
"obvious" interpretation, multiplying y by 2, using it for one cos call,
then multiplying it by 2 again and using it for the other cos call.
The file has other (valid) tests that side-effects don't block
optimisation, such as:
if (cosf((y*=3, -x)) != cosf((y*=3,x)))
link_error ();
so this patch simply removes this instance.
Tested on x86_64-linux-gnu, aarch64-linux-gnu and arm-linux-gnueabi.
OK to install?
Thanks,
Richard
gcc/testsuite/
* gcc.dg/builtins-20.c: Remove undefined behavior.
diff --git a/gcc/testsuite/gcc.dg/builtins-20.c
b/gcc/testsuite/gcc.dg/builtins-20.c
index 43aa71b..2b63428 100644
--- a/gcc/testsuite/gcc.dg/builtins-20.c
+++ b/gcc/testsuite/gcc.dg/builtins-20.c
@@ -122,7 +122,7 @@ void test2(double x, double y)
if (cos((y*=3, -x)) != cos((y*=3,x)))
link_error ();
- if (cos((y*=2, -fabs(tan(x/-y)))) != cos((y*=2,tan(x/y))))
+ if (cos(-fabs(tan(x/-y))) != cos(tan(x/y)))
link_error ();
if (cos(copysign(x,y)) != cos(x))
@@ -350,7 +350,7 @@ void test2f(float x, float y)
if (cosf((y*=3, -x)) != cosf((y*=3,x)))
link_error ();
- if (cosf((y*=2, -fabsf(tanf(x/-y)))) != cosf((y*=2,tanf(x/y))))
+ if (cosf(-fabsf(tanf(x/-y))) != cosf(tanf(x/y)))
link_error ();
if (cosf(copysignf(x,y)) != cosf(x))
@@ -577,7 +577,7 @@ void test2l(long double x, long double y)
if (cosl((y*=3, -x)) != cosl((y*=3,x)))
link_error ();
- if (cosl((y*=2, -fabsl(tanl(x/-y)))) != cosl((y*=2,tanl(x/y))))
+ if (cosl(-fabsl(tanl(x/-y))) != cosl(tanl(x/y)))
link_error ();
if (cosl(copysignl(x,y)) != cosl(x))
