expl lacks precision musl libc 1.2.2/arm64, musl libc 1.2.2/s390x.
Fortunately the configure test meant for NetBSD already catches it.
2021-01-31 Bruno Haible <br...@clisp.org>
expl: Document musl libc bug.
* doc/posix-functions/expl.texi: Document musl libc bug.
* m4/expl.m4 (gl_FUNC_EXPL): Update comment and cross
compilation guess.
diff --git a/doc/posix-functions/expl.texi b/doc/posix-functions/expl.texi
index d0810b2..f70589f 100644
--- a/doc/posix-functions/expl.texi
+++ b/doc/posix-functions/expl.texi
@@ -23,7 +23,7 @@ MSVC 14.
@item
This function produces results which are accurate to only 16 digits on some
platforms:
-NetBSD 9.0.
+musl libc 1.2.2/arm64, musl libc 1.2.2/s390x, NetBSD 9.0.
@end itemize
Portability problems not fixed by Gnulib:
diff --git a/m4/expl.m4 b/m4/expl.m4
index 0ed62ab..9e7bfa7 100644
--- a/m4/expl.m4
+++ b/m4/expl.m4
@@ -1,4 +1,4 @@
-# expl.m4 serial 17
+# expl.m4 serial 18
dnl Copyright (C) 2010-2021 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
@@ -129,7 +129,7 @@ int main (int argc, char *argv[])
if (isnan (expl (x1)) || isnan (expl (x2)) || isnan (expl (x3)))
result |= 2;
}
- /* This test fails on NetBSD 9.0. */
+ /* This test fails on musl 1.2.2/arm64, musl 1.2.2/s390x, NetBSD 9.0. */
{
const long double TWO_LDBL_MANT_DIG = /* 2^LDBL_MANT_DIG */
(long double) (1U << ((LDBL_MANT_DIG - 1) / 5))
@@ -150,8 +150,8 @@ int main (int argc, char *argv[])
[case "$host_os" in
# Guess yes on glibc systems.
*-gnu* | gnu*) gl_cv_func_expl_works="guessing yes" ;;
- # Guess yes on musl systems.
- *-musl*) gl_cv_func_expl_works="guessing yes" ;;
+ # Guess no on musl systems.
+ *-musl*) gl_cv_func_expl_works="guessing no" ;;
# Guess yes on native Windows.
mingw*) gl_cv_func_expl_works="guessing yes" ;;
# If we don't know, obey --enable-cross-guesses.
