Since TS 18661-1 has been integrated into C2X, this patch makes C2X
imply -fno-fp-int-builtin-inexact.
Bootstrapped with no regressions on x86_64-pc-linux-gnu. Applied to
mainline.
gcc:
2019-10-08 Joseph Myers <jos...@codesourcery.com>
* doc/invoke.texi (-ffp-int-builtin-inexact): Document
-fno-fp-int-builtin-inexact default for C2X.
gcc/c-family:
2019-10-08 Joseph Myers <jos...@codesourcery.com>
* c-opts.c (c_common_post_options): Set
-fno-fp-int-builtin-inexact for C2X.
gcc/testsuite:
2019-10-08 Joseph Myers <jos...@codesourcery.com>
* gcc.dg/torture/builtin-fp-int-inexact-c2x.c: New test.
Index: gcc/c-family/c-opts.c
===================================================================
--- gcc/c-family/c-opts.c (revision 276655)
+++ gcc/c-family/c-opts.c (working copy)
@@ -826,6 +826,12 @@ c_common_post_options (const char **pfilename)
else
flag_permitted_flt_eval_methods = PERMITTED_FLT_EVAL_METHODS_C11;
+ /* C2X Annex F does not permit certain built-in functions to raise
+ "inexact". */
+ if (flag_isoc2x
+ && !global_options_set.x_flag_fp_int_builtin_inexact)
+ flag_fp_int_builtin_inexact = 0;
+
/* By default we use C99 inline semantics in GNU99 or C99 mode. C99
inline semantics are not supported in GNU89 or C89 mode. */
if (flag_gnu89_inline == -1)
Index: gcc/doc/invoke.texi
===================================================================
--- gcc/doc/invoke.texi (revision 276655)
+++ gcc/doc/invoke.texi (working copy)
@@ -10810,12 +10810,12 @@ Do not allow the built-in functions @code{ceil}, @
double} variants, to generate code that raises the ``inexact''
floating-point exception for noninteger arguments. ISO C99 and C11
allow these functions to raise the ``inexact'' exception, but ISO/IEC
-TS 18661-1:2014, the C bindings to IEEE 754-2008, does not allow these
-functions to do so.
+TS 18661-1:2014, the C bindings to IEEE 754-2008, as integrated into
+ISO C2X, does not allow these functions to do so.
The default is @option{-ffp-int-builtin-inexact}, allowing the
-exception to be raised. This option does nothing unless
-@option{-ftrapping-math} is in effect.
+exception to be raised, unless C2X or a later C standard is selected.
+This option does nothing unless @option{-ftrapping-math} is in effect.
Even if @option{-fno-fp-int-builtin-inexact} is used, if the functions
generate a call to a library function then the ``inexact'' exception
Index: gcc/testsuite/gcc.dg/torture/builtin-fp-int-inexact-c2x.c
===================================================================
--- gcc/testsuite/gcc.dg/torture/builtin-fp-int-inexact-c2x.c (nonexistent)
+++ gcc/testsuite/gcc.dg/torture/builtin-fp-int-inexact-c2x.c (working copy)
@@ -0,0 +1,7 @@
+/* Test C2X enables -fno-fp-int-builtin-inexact. */
+/* { dg-do run } */
+/* { dg-options "-std=c2x" } */
+/* { dg-add-options c99_runtime } */
+/* { dg-require-effective-target fenv_exceptions } */
+
+#include "builtin-fp-int-inexact.c"
--
Joseph S. Myers
jos...@codesourcery.com
