[PATCH, fortran ieee]: PR 88678, Many gfortran.dg/ieee/ieee_X.f90 test cases fail starting with r267465

[Uros Bizjak]

On Wed, Jan 30, 2019 at 10:37 AM Uros Bizjak <ubizjak@gmail.com> wrote:

> > Your decription suggests that this fixes PR fortran/88678.
> > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88678
>
> Actually, additional patch is needed to fully fix PR88678.
> support_fpu_trap enables and disables exceptions and this may fire
> spurious exceptions. Just assume that all supported flags can generate
> exceptions, as is done in the additional patch, posted to PR88678.

The remaining ieee_*.f90 tests and large_1.f90 test failures on
powerpc64 are fixed by the attached patch.

2019-01-30  Uroš Bizjak  <ubizjak@gmail.com>

    PR fortran/88678
    * config/fpu-glibc.h (support_fpu_trap): Do not try to enable
    exceptions to determine if exception is supported.

Bootstrapped and regression tested on x86_64-linux-gnu {,-m32} (with
appropriate config.host tweak to select fpu-glibc.header),
alphaev68-linux-gnu and as reported in the PR, on
powerpc64le-linux-gnu by Peter.

OK for mainline?

Uros.
-------------- next part --------------
diff --git a/libgfortran/config/fpu-glibc.h b/libgfortran/config/fpu-glibc.h
index c24bb6cbcd92..df2588e038d8 100644
--- a/libgfortran/config/fpu-glibc.h
+++ b/libgfortran/config/fpu-glibc.h
@@ -121,41 +129,7 @@ get_fpu_trap_exceptions (void)
 int
 support_fpu_trap (int flag)
 {
-  int exceptions = 0;
-  int old;
-
-  if (!support_fpu_flag (flag))
-    return 0;
-
-#ifdef FE_INVALID
-  if (flag & GFC_FPE_INVALID) exceptions |= FE_INVALID;
-#endif
-
-#ifdef FE_DIVBYZERO
-  if (flag & GFC_FPE_ZERO) exceptions |= FE_DIVBYZERO;
-#endif
-
-#ifdef FE_OVERFLOW
-  if (flag & GFC_FPE_OVERFLOW) exceptions |= FE_OVERFLOW;
-#endif
-
-#ifdef FE_UNDERFLOW
-  if (flag & GFC_FPE_UNDERFLOW) exceptions |= FE_UNDERFLOW;
-#endif
-
-#ifdef FE_DENORMAL
-  if (flag & GFC_FPE_DENORMAL) exceptions |= FE_DENORMAL;
-#endif
-
-#ifdef FE_INEXACT
-  if (flag & GFC_FPE_INEXACT) exceptions |= FE_INEXACT;
-#endif
-
-  old = feenableexcept (exceptions);
-  if (old == -1)
-    return 0;
-  fedisableexcept (exceptions & ~old);
-  return 1;
+  return support_fpu_flag (flag);
 }