https://github.com/AaronBallman created https://github.com/llvm/llvm-project/pull/96659
This is in support of WG14 N2848 which only define the macros if infinity and nan are supported, so use of -ffinite-math will cause the macros to not be defined. >From b59c7f8c91d7c128975554d90bef3657ce3b2728 Mon Sep 17 00:00:00 2001 From: Aaron Ballman <aa...@aaronballman.com> Date: Tue, 25 Jun 2024 10:52:56 -0400 Subject: [PATCH 1/2] [C23] Add INFINITY and NAN macros to <float.h> This is in support of WG14 N2848 which only define the macros if infinity and nan are supported, so use of -ffinite-math will cause the macros to not be defined. --- clang/docs/ReleaseNotes.rst | 5 +++++ clang/lib/Headers/float.h | 6 ++++++ clang/test/Headers/float.c | 29 +++++++++++++++++++++++++++++ 3 files changed, 40 insertions(+) diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst index df579ae398c5e..45c9a2cc47b09 100644 --- a/clang/docs/ReleaseNotes.rst +++ b/clang/docs/ReleaseNotes.rst @@ -336,6 +336,11 @@ C23 Feature Support - Properly promote bit-fields of bit-precise integer types to the field's type rather than to ``int``. #GH87641 +- Added the ``INFINITY`` and ``NAN`` macros to Clang's ``<float.h>`` + freestanding implementation; these macros were defined in C99 but Clang + implements the macros as described by C23 in + `WG14 N2848 <https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2848.pdf>`_. + Non-comprehensive list of changes in this release ------------------------------------------------- diff --git a/clang/lib/Headers/float.h b/clang/lib/Headers/float.h index 642c8f06cc938..929c0854a865b 100644 --- a/clang/lib/Headers/float.h +++ b/clang/lib/Headers/float.h @@ -47,6 +47,8 @@ (defined(__cplusplus) && __cplusplus >= 201103L) || \ (__STDC_HOSTED__ && defined(_AIX) && defined(_ALL_SOURCE)) # undef DECIMAL_DIG +# undef INFINITY +# undef NAN # endif # undef FLT_DIG # undef DBL_DIG @@ -93,6 +95,10 @@ #if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 199901L) || \ (defined(__cplusplus) && __cplusplus >= 201103L) #define FLT_EVAL_METHOD __FLT_EVAL_METHOD__ +#if defined(__FINITE_MATH_ONLY__) && !__FINITE_MATH_ONLY__ +# define INFINITY (__builtin_infinity()) +# define NAN (__builtin_nan("")) +#endif #endif #define FLT_ROUNDS (__builtin_flt_rounds()) #define FLT_RADIX __FLT_RADIX__ diff --git a/clang/test/Headers/float.c b/clang/test/Headers/float.c index 70c11b0537537..8dfbc32521ade 100644 --- a/clang/test/Headers/float.c +++ b/clang/test/Headers/float.c @@ -1,9 +1,13 @@ // RUN: %clang_cc1 -fsyntax-only -verify -std=c89 -ffreestanding %s // RUN: %clang_cc1 -fsyntax-only -verify -std=c99 -ffreestanding %s // RUN: %clang_cc1 -fsyntax-only -verify -std=c11 -ffreestanding %s +// RUN: %clang_cc1 -fsyntax-only -verify -std=c23 -ffreestanding %s +// RUN: %clang_cc1 -fsyntax-only -verify -std=c23 -ffreestanding -ffinite-math-only %s // RUN: %clang_cc1 -fsyntax-only -verify -xc++ -std=c++11 -ffreestanding %s // RUN: %clang_cc1 -fsyntax-only -verify -xc++ -std=c++14 -ffreestanding %s // RUN: %clang_cc1 -fsyntax-only -verify -xc++ -std=c++17 -ffreestanding %s +// RUN: %clang_cc1 -fsyntax-only -verify -xc++ -std=c++23 -ffreestanding %s +// RUN: %clang_cc1 -fsyntax-only -verify -xc++ -std=c++23 -ffreestanding -ffinite-math-only %s // expected-no-diagnostics /* Basic floating point conformance checks against: @@ -107,10 +111,35 @@ #elif DECIMAL_DIG < 10 #error "Mandatory macro DECIMAL_DIG is invalid." #endif + + #if __FINITE_MATH_ONLY__ == 0 + #ifndef INFINITY + #error "Mandatory macro INFINITY is missing." + #endif + #ifndef NAN + #error "Mandatory macro NAN is missing." + #endif + #else + #ifdef INFINITY + #error "Macro INFINITY should not be defined." + #endif + + #ifdef NAN + #error "Macro NAN should not be defined." + #endif + #endif #else #ifdef DECIMAL_DIG #error "Macro DECIMAL_DIG should not be defined." #endif + + #ifdef INFINITY + #error "Macro INFINITY should not be defined." + #endif + + #ifdef NAN + #error "Macro NAN should not be defined." + #endif #endif >From 86055e3ecb25befdffdf17f2a1eb8b9c704a1e7a Mon Sep 17 00:00:00 2001 From: Aaron Ballman <aa...@aaronballman.com> Date: Tue, 25 Jun 2024 10:55:03 -0400 Subject: [PATCH 2/2] Update the status page --- clang/www/c_status.html | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/clang/www/c_status.html b/clang/www/c_status.html index 04c1df9ebc050..bc37f8cd5e404 100644 --- a/clang/www/c_status.html +++ b/clang/www/c_status.html @@ -991,7 +991,7 @@ <h2 id="c2x">C23 implementation status</h2> <tr> <td>Contradiction about INFINITY macro</td> <td><a href="https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2848.pdf";>N2848</a></td> - <td class="unknown" align="center">Unknown</td> + <td class="unreleased" align="center">Clang 19</td> </tr> <tr> <td>Require exact-width integer type interfaces</td> _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
