Set -ffp-contract=off for libffi.call/many.c

[Marcus Shawcroft <marcus.shawcroft@arm.com>]

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Hi,

The review of this patch ran out of stream:

https://sourceware.org/ml/libffi-discuss/2013/msg00128.html

The proposed solution would not work when testing with a none GCC 
compiler.  Constraining the dg-option was tricky because the mechanism 
available allows matching against the target triple not the compiler and 
in this particular scenario the issue was the compiler, not the target.

The purpose of the test is to ensure that the arguments are correctly 
passed via two alternative mechanisms.  The actual sequence of 
operations used to combine all the arguments into a return value is 
largely irrelevant.

Therefore the other route here is to adjust the computation used to 
remove the opportunity for the compiler to choose a fused multiply.

Proposed patch attached.

OK?

2013-10-11  Marcus Shawcroft  <marcus.shawcroft@arm.com>

         * testsuite/libffi.call/many.c (many): Replace * with +.

Thanks
/Marcus

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diff --git a/testsuite/libffi.call/many.c b/testsuite/libffi.call/many.c
index 67a367f..11818e6 100644
--- a/testsuite/libffi.call/many.c
+++ b/testsuite/libffi.call/many.c
@@ -32,7 +32,7 @@ static float many(float f1,
 	 (double) f11, (double) f12, (double) f13);
 #endif
 
-  return ((f1/f2+f3/f4+f5/f6+f7/f8+f9/f10+f11/f12) * f13);
+  return f1/f2+f3/f4+f5/f6+f7/f8+f9/f10+f11/f12+f13;
 }
 
 int main (void)