Make bits/math-finite.h conditions match other headers (bug 19205) [committed]

[Joseph Myers <joseph at codesourcery dot com>]

bits/math-finite.h declares -ffinite-math-only variants of various
functions under conditions not matching those under which the normal
versions are declared.

* math.h only ever includes bits/mathcalls.h to declare float and long
  double functions if __USE_ISOC99, but bits/math-finite.h declares
  some float functions regardless (long double ones are conditioned on
  __MATH_DECLARE_LDOUBLE).  (For C90 functions this isn't a
  conformance bug because C90 reserves the float and long double
  names, but is still contrary to good glibc practice.  For some other
  functions in older XSI standards it *is* a conformance bug.)

* Some functions are defined as inlines using lgamma_r functions under
  conditions where those lgamma_r functions are not themselves
  declared.

* hypot is declared under __USE_XOPEN || __USE_ISOC99 in
  bits/mathcalls.h, __USE_ISOC99 only in bits/math-finite.h.

* float and long double versions of Bessel functions should be limited
  to __USE_MISC (as in bug 18977).

* gamma should not be declared for __USE_XOPEN2K (as in bug 18967).

* remainder should be restricted to __USE_XOPEN_EXTENDED ||
  __USE_ISOC99, not unconditional.

* scalb should not be declared for __USE_XOPEN2K8, and scalbf and
  scalbl are non-POSIX (as in bug 18967).

This patch fixes all these issues (it doesn't seem worth splitting
them into separate patches or bugs).  I put __USE_ISOC99 conditionals,
where needed, around both float and long double declarations, even
though formally redundant around the long double declarations because
__MATH_DECLARE_LDOUBLE isn't defined without __USE_ISOC99; it seemed
clearer that way.  The missing declarations of lgamma_r functions are
dealt with by directly using declarations of __lgamma*_r_finite, in
the implementation namespace, rather than having the inlines rely on
asm redirection of lgamma*_r.

After this patch, there are some apparently redundant nested
__USE_ISOC99 conditionals in lgamma / gamma definitions.  These
actually reflect a separate bug (the correct condition for the lgamma
inline functions to set signgam is __USE_MISC || __USE_XOPEN, the
condition under which signgam is declared, rather than disabling
setting it if __USE_ISOC99, which includes XSI POSIX versions for
which signgam *should* be set).  They'll be fixed as part of a fix for
that bug, which will also add tests for these inlines.  I've put a
note about more general conform/ test coverage for -ffinite-math-only
on
<https://sourceware.org/glibc/wiki/Development_Todo/Master#conformtest_improvements>,
alongside other options for which this is also relevant (some of which
have also had such bugs in the past relating to mismatched
conditionals).

I also intend to enable the main libm-test.inc tests for the
math-finite.h functions, but some other bugs in __*_finite need fixing
first.

Tested for x86_64 and x86.  Committed.

2015-11-05  Joseph Myers  <joseph@codesourcery.com>

	[BZ #19205]
	* math/bits/math-finite.h (acosf): Condition declaration on
	[__USE_ISOC99].
	(acosl): Likewise.
	(acoshf): Likewise.
	(acoshl): Likewise.
	(asinf): Likewise.
	(asinl): Likewise.
	(atan2f): Likewise.
	(atan2l): Likewise.
	(atanhf): Likewise.
	(atanhl): Likewise.
	(coshf): Likewise.
	(coshl): Likewise.
	(expf): Likewise.
	(expl): Likewise.
	(fmodf): Likewise.
	(fmodl): Likewise.
	(hypot): Change condition to [__USE_XOPEN || __USE_ISOC99].
	(j0f): Change condition to [__USE_MISC && __USE_ISOC99].
	(j0l): Likewise.
	(y0f): Likewise.
	(y0l): Likewise.
	(j1f): Likewise.
	(j1l): Likewise.
	(y1f): Likewise.
	(y1l): Likewise.
	(jnf): Likewise.
	(jnl): Likewise.
	(ynf): Likewise.
	(ynl): Likewise.
	(lgammaf_r): Condition declaration on [__USE_ISOC99].
	(lgammal_r): Likewise.
	(__lgamma_r_finite): New declaration.
	(__lgammaf_r_finite): Likewise.
	(__lgammal_r_finite): Likewise.
	(lgamma): Use __lgamma_r_finite.
	(lgammaf): Condition definition on [__USE_ISOC99].  Use
	__lgammaf_r_finite.
	(lgammal): Condition definition on [__USE_ISOC99].  Use
	__lgammal_r_finite.
	(gamma): Do not define for [!__USE_MISC && __USE_XOPEN2K].  Use
	__lgamma_r_finite.
	(gammaf): Condition definition on [__USE_ISOC99].  Use
	__lgammaf_r_finite.
	(gammal): Condition definition on [__USE_ISOC99].  Use
	__lgammal_r_finite.
	(logf): Condition declaration on [__USE_ISOC99].
	(logl): Likewise.
	(log10f): Likewise.
	(log10l): Likewise.
	(ldexpf): Likewise.
	(ldexpl): Likewise.
	(powf): Likewise.
	(powl): Likewise.
	(remainder): Condition declaration on [__USE_XOPEN_EXTENDED ||
	__USE_ISOC99].
	(remainderf): Condition declaration on [__USE_ISOC99].
	(remainderl): Likewise.
	(scalb): Do not declare for [!__USE_MISC && __USE_XOPEN2K8].
	(scalbf): Change condition to [__USE_MISC && __USE_ISOC99].
	(scalbl): Likewise.
	(sinhf): Condition declaration on [__USE_ISOC99].
	(sinhl): Likewise.
	(sqrtf): Likewise.
	(sqrtl): Likewise.

diff --git a/math/bits/math-finite.h b/math/bits/math-finite.h
index a9f4bf6..e5f11b2 100644
--- a/math/bits/math-finite.h
+++ b/math/bits/math-finite.h
@@ -22,18 +22,22 @@
 
 /* acos.  */
 extern double __REDIRECT_NTH (acos, (double), __acos_finite);
+#ifdef __USE_ISOC99
 extern float __REDIRECT_NTH (acosf, (float), __acosf_finite);
-#ifdef __MATH_DECLARE_LDOUBLE
-# ifdef __NO_LONG_DOUBLE_MATH
+# ifdef __MATH_DECLARE_LDOUBLE
+#  ifdef __NO_LONG_DOUBLE_MATH
 extern long double __REDIRECT_NTH (acosl, (long double), __acos_finite);
-# else
+#  else
 extern long double __REDIRECT_NTH (acosl, (long double), __acosl_finite);
+#  endif
 # endif
 #endif
 
 #if defined __USE_XOPEN_EXTENDED || defined __USE_ISOC99
 /* acosh.  */
 extern double __REDIRECT_NTH (acosh, (double), __acosh_finite);
+#endif
+#ifdef __USE_ISOC99
 extern float __REDIRECT_NTH (acoshf, (float), __acoshf_finite);
 # ifdef __MATH_DECLARE_LDOUBLE
 #  ifdef __NO_LONG_DOUBLE_MATH
@@ -46,31 +50,37 @@ extern long double __REDIRECT_NTH (acoshl, (long double), __acoshl_finite);
 
 /* asin.  */
 extern double __REDIRECT_NTH (asin, (double), __asin_finite);
+#ifdef __USE_ISOC99
 extern float __REDIRECT_NTH (asinf, (float), __asinf_finite);
-#ifdef __MATH_DECLARE_LDOUBLE
-# ifdef __NO_LONG_DOUBLE_MATH
+# ifdef __MATH_DECLARE_LDOUBLE
+#  ifdef __NO_LONG_DOUBLE_MATH
 extern long double __REDIRECT_NTH (asinl, (long double), __asin_finite);
-# else
+#  else
 extern long double __REDIRECT_NTH (asinl, (long double), __asinl_finite);
+#  endif
 # endif
 #endif
 
 /* atan2.  */
 extern double __REDIRECT_NTH (atan2, (double, double), __atan2_finite);
+#ifdef __USE_ISOC99
 extern float __REDIRECT_NTH (atan2f, (float, float), __atan2f_finite);
-#ifdef __MATH_DECLARE_LDOUBLE
-# ifdef __NO_LONG_DOUBLE_MATH
+# ifdef __MATH_DECLARE_LDOUBLE
+#  ifdef __NO_LONG_DOUBLE_MATH
 extern long double __REDIRECT_NTH (atan2l, (long double, long double),
 				   __atan2_finite);
-# else
+#  else
 extern long double __REDIRECT_NTH (atan2l, (long double, long double),
 				   __atan2l_finite);
+#  endif
 # endif
 #endif
 
 #if defined __USE_XOPEN_EXTENDED || defined __USE_ISOC99
 /* atanh.  */
 extern double __REDIRECT_NTH (atanh, (double), __atanh_finite);
+#endif
+#ifdef __USE_ISOC99
 extern float __REDIRECT_NTH (atanhf, (float), __atanhf_finite);
 # ifdef __MATH_DECLARE_LDOUBLE
 #  ifdef __NO_LONG_DOUBLE_MATH
@@ -83,23 +93,27 @@ extern long double __REDIRECT_NTH (atanhl, (long double), __atanhl_finite);
 
 /* cosh.  */
 extern double __REDIRECT_NTH (cosh, (double), __cosh_finite);
+#ifdef __USE_ISOC99
 extern float __REDIRECT_NTH (coshf, (float), __coshf_finite);
-#ifdef __MATH_DECLARE_LDOUBLE
-# ifdef __NO_LONG_DOUBLE_MATH
+# ifdef __MATH_DECLARE_LDOUBLE
+#  ifdef __NO_LONG_DOUBLE_MATH
 extern long double __REDIRECT_NTH (coshl, (long double), __cosh_finite);
-# else
+#  else
 extern long double __REDIRECT_NTH (coshl, (long double), __coshl_finite);
+#  endif
 # endif
 #endif
 
 /* exp.  */
 extern double __REDIRECT_NTH (exp, (double), __exp_finite);
+#ifdef __USE_ISOC99
 extern float __REDIRECT_NTH (expf, (float), __expf_finite);
-#ifdef __MATH_DECLARE_LDOUBLE
-# ifdef __NO_LONG_DOUBLE_MATH
+# ifdef __MATH_DECLARE_LDOUBLE
+#  ifdef __NO_LONG_DOUBLE_MATH
 extern long double __REDIRECT_NTH (expl, (long double), __exp_finite);
-# else
+#  else
 extern long double __REDIRECT_NTH (expl, (long double), __expl_finite);
+#  endif
 # endif
 #endif
 
@@ -142,20 +156,24 @@ extern long double __REDIRECT_NTH (exp2l, (long double), __exp2l_finite);
 
 /* fmod.  */
 extern double __REDIRECT_NTH (fmod, (double, double), __fmod_finite);
+#ifdef __USE_ISOC99
 extern float __REDIRECT_NTH (fmodf, (float, float), __fmodf_finite);
-#ifdef __MATH_DECLARE_LDOUBLE
-# ifdef __NO_LONG_DOUBLE_MATH
+# ifdef __MATH_DECLARE_LDOUBLE
+#  ifdef __NO_LONG_DOUBLE_MATH
 extern long double __REDIRECT_NTH (fmodl, (long double, long double),
 				   __fmod_finite);
-# else
+#  else
 extern long double __REDIRECT_NTH (fmodl, (long double, long double),
 				   __fmodl_finite);
+#  endif
 # endif
 #endif
 
-#ifdef __USE_ISOC99
+#if defined __USE_XOPEN || defined __USE_ISOC99
 /* hypot.  */
 extern double __REDIRECT_NTH (hypot, (double, double), __hypot_finite);
+#endif
+#ifdef __USE_ISOC99
 extern float __REDIRECT_NTH (hypotf, (float, float), __hypotf_finite);
 # ifdef __MATH_DECLARE_LDOUBLE
 #  ifdef __NO_LONG_DOUBLE_MATH
@@ -171,6 +189,8 @@ extern long double __REDIRECT_NTH (hypotl, (long double, long double),
 #if defined __USE_MISC || defined __USE_XOPEN
 /* j0.  */
 extern double __REDIRECT_NTH (j0, (double), __j0_finite);
+#endif
+#if defined __USE_MISC && defined __USE_ISOC99
 extern float __REDIRECT_NTH (j0f, (float), __j0f_finite);
 # ifdef __MATH_DECLARE_LDOUBLE
 #  ifdef __NO_LONG_DOUBLE_MATH
@@ -179,9 +199,13 @@ extern long double __REDIRECT_NTH (j0l, (long double), __j0_finite);
 extern long double __REDIRECT_NTH (j0l, (long double), __j0l_finite);
 #  endif
 # endif
+#endif
 
+#if defined __USE_MISC || defined __USE_XOPEN
 /* y0.  */
 extern double __REDIRECT_NTH (y0, (double), __y0_finite);
+#endif
+#if defined __USE_MISC && defined __USE_ISOC99
 extern float __REDIRECT_NTH (y0f, (float), __y0f_finite);
 # ifdef __MATH_DECLARE_LDOUBLE
 #  ifdef __NO_LONG_DOUBLE_MATH
@@ -190,9 +214,13 @@ extern long double __REDIRECT_NTH (y0l, (long double), __y0_finite);
 extern long double __REDIRECT_NTH (y0l, (long double), __y0l_finite);
 #  endif
 # endif
+#endif
 
+#if defined __USE_MISC || defined __USE_XOPEN
 /* j1.  */
 extern double __REDIRECT_NTH (j1, (double), __j1_finite);
+#endif
+#if defined __USE_MISC && defined __USE_ISOC99
 extern float __REDIRECT_NTH (j1f, (float), __j1f_finite);
 # ifdef __MATH_DECLARE_LDOUBLE
 #  ifdef __NO_LONG_DOUBLE_MATH
@@ -201,9 +229,13 @@ extern long double __REDIRECT_NTH (j1l, (long double), __j1_finite);
 extern long double __REDIRECT_NTH (j1l, (long double), __j1l_finite);
 #  endif
 # endif
+#endif
 
+#if defined __USE_MISC || defined __USE_XOPEN
 /* y1.  */
 extern double __REDIRECT_NTH (y1, (double), __y1_finite);
+#endif
+#if defined __USE_MISC && defined __USE_ISOC99
 extern float __REDIRECT_NTH (y1f, (float), __y1f_finite);
 # ifdef __MATH_DECLARE_LDOUBLE
 #  ifdef __NO_LONG_DOUBLE_MATH
@@ -212,9 +244,13 @@ extern long double __REDIRECT_NTH (y1l, (long double), __y1_finite);
 extern long double __REDIRECT_NTH (y1l, (long double), __y1l_finite);
 #  endif
 # endif
+#endif
 
+#if defined __USE_MISC || defined __USE_XOPEN
 /* jn.  */
 extern double __REDIRECT_NTH (jn, (int, double), __jn_finite);
+#endif
+#if defined __USE_MISC && defined __USE_ISOC99
 extern float __REDIRECT_NTH (jnf, (int, float), __jnf_finite);
 # ifdef __MATH_DECLARE_LDOUBLE
 #  ifdef __NO_LONG_DOUBLE_MATH
@@ -223,9 +259,13 @@ extern long double __REDIRECT_NTH (jnl, (int, long double), __jn_finite);
 extern long double __REDIRECT_NTH (jnl, (int, long double), __jnl_finite);
 #  endif
 # endif
+#endif
 
+#if defined __USE_MISC || defined __USE_XOPEN
 /* yn.  */
 extern double __REDIRECT_NTH (yn, (int, double), __yn_finite);
+#endif
+#if defined __USE_MISC && defined __USE_ISOC99
 extern float __REDIRECT_NTH (ynf, (int, float), __ynf_finite);
 # ifdef __MATH_DECLARE_LDOUBLE
 #  ifdef __NO_LONG_DOUBLE_MATH
@@ -239,18 +279,29 @@ extern long double __REDIRECT_NTH (ynl, (int, long double), __ynl_finite);
 #ifdef __USE_MISC
 /* lgamma_r.  */
 extern double __REDIRECT_NTH (lgamma_r, (double, int *), __lgamma_r_finite);
+# ifdef __USE_ISOC99
 extern float __REDIRECT_NTH (lgammaf_r, (float, int *), __lgammaf_r_finite);
-# ifdef __MATH_DECLARE_LDOUBLE
-#  ifdef __NO_LONG_DOUBLE_MATH
+#  ifdef __MATH_DECLARE_LDOUBLE
+#   ifdef __NO_LONG_DOUBLE_MATH
 extern long double __REDIRECT_NTH (lgammal_r, (long double, int *),
 				   __lgamma_r_finite);
-#  else
+#   else
 extern long double __REDIRECT_NTH (lgammal_r, (long double, int *),
 				   __lgammal_r_finite);
+#   endif
 #  endif
 # endif
 #endif
 
+extern double __lgamma_r_finite (double, int *);
+extern float __lgammaf_r_finite (float, int *);
+#ifdef __NO_LONG_DOUBLE_MATH
+extern long double __REDIRECT_NTH (__lgammal_r_finite, (long double, int *),
+				   __lgamma_r_finite);
+#else
+extern long double __lgammal_r_finite (long double, int *);
+#endif
+
 #if ((defined __USE_XOPEN || defined __USE_ISOC99) \
      && defined __extern_always_inline)
 /* lgamma.  */
@@ -258,18 +309,20 @@ __extern_always_inline double __NTH (lgamma (double __d))
 {
 # ifdef __USE_ISOC99
   int __local_signgam = 0;
-  return lgamma_r (__d, &__local_signgam);
+  return __lgamma_r_finite (__d, &__local_signgam);
 # else
-  return lgamma_r (__d, &signgam);
+  return __lgamma_r_finite (__d, &signgam);
 # endif
 }
+#endif
+#if defined __USE_ISOC99 && defined __extern_always_inline
 __extern_always_inline float __NTH (lgammaf (float __d))
 {
 # ifdef __USE_ISOC99
   int __local_signgam = 0;
-  return lgammaf_r (__d, &__local_signgam);
+  return __lgammaf_r_finite (__d, &__local_signgam);
 # else
-  return lgammaf_r (__d, &signgam);
+  return __lgammaf_r_finite (__d, &signgam);
 # endif
 }
 # ifdef __MATH_DECLARE_LDOUBLE
@@ -277,67 +330,73 @@ __extern_always_inline long double __NTH (lgammal (long double __d))
 {
 # ifdef __USE_ISOC99
   int __local_signgam = 0;
-  return lgammal_r (__d, &__local_signgam);
+  return __lgammal_r_finite (__d, &__local_signgam);
 # else
-  return lgammal_r (__d, &signgam);
+  return __lgammal_r_finite (__d, &signgam);
 # endif
 }
 # endif
 #endif
 
-#if ((defined __USE_MISC || defined __USE_XOPEN) \
+#if ((defined __USE_MISC || (defined __USE_XOPEN && !defined __USE_XOPEN2K)) \
      && defined __extern_always_inline)
 /* gamma.  */
 __extern_always_inline double __NTH (gamma (double __d))
 {
 # ifdef __USE_ISOC99
   int __local_signgam = 0;
-  return lgamma_r (__d, &__local_signgam);
+  return __lgamma_r_finite (__d, &__local_signgam);
 # else
-  return lgamma_r (__d, &signgam);
+  return __lgamma_r_finite (__d, &signgam);
 # endif
 }
+# ifdef __USE_ISOC99
 __extern_always_inline float __NTH (gammaf (float __d))
 {
-# ifdef __USE_ISOC99
+#  ifdef __USE_ISOC99
   int __local_signgam = 0;
-  return lgammaf_r (__d, &__local_signgam);
-# else
-  return lgammaf_r (__d, &signgam);
-# endif
+  return __lgammaf_r_finite (__d, &__local_signgam);
+#  else
+  return __lgammaf_r_finite (__d, &signgam);
+#  endif
 }
-# ifdef __MATH_DECLARE_LDOUBLE
+#  ifdef __MATH_DECLARE_LDOUBLE
 __extern_always_inline long double __NTH (gammal (long double __d))
 {
-#  ifdef __USE_ISOC99
+#   ifdef __USE_ISOC99
   int __local_signgam = 0;
-  return lgammal_r (__d, &__local_signgam);
-#  else
-  return lgammal_r (__d, &signgam);
-#  endif
+  return __lgammal_r_finite (__d, &__local_signgam);
+#   else
+  return __lgammal_r_finite (__d, &signgam);
+#   endif
 }
+#  endif
 # endif
 #endif
 
 /* log.  */
 extern double __REDIRECT_NTH (log, (double), __log_finite);
+#ifdef __USE_ISOC99
 extern float __REDIRECT_NTH (logf, (float), __logf_finite);
-#ifdef __MATH_DECLARE_LDOUBLE
-# ifdef __NO_LONG_DOUBLE_MATH
+# ifdef __MATH_DECLARE_LDOUBLE
+#  ifdef __NO_LONG_DOUBLE_MATH
 extern long double __REDIRECT_NTH (logl, (long double), __log_finite);
-# else
+#  else
 extern long double __REDIRECT_NTH (logl, (long double), __logl_finite);
+#  endif
 # endif
 #endif
 
 /* log10.  */
 extern double __REDIRECT_NTH (log10, (double), __log10_finite);
+#ifdef __USE_ISOC99
 extern float __REDIRECT_NTH (log10f, (float), __log10f_finite);
-#ifdef __MATH_DECLARE_LDOUBLE
-# ifdef __NO_LONG_DOUBLE_MATH
+# ifdef __MATH_DECLARE_LDOUBLE
+#  ifdef __NO_LONG_DOUBLE_MATH
 extern long double __REDIRECT_NTH (log10l, (long double), __log10_finite);
-# else
+#  else
 extern long double __REDIRECT_NTH (log10l, (long double), __log10l_finite);
+#  endif
 # endif
 #endif
 
@@ -356,40 +415,51 @@ extern long double __REDIRECT_NTH (log2l, (long double), __log2l_finite);
 
 /* ldexp.  */
 extern double __REDIRECT_NTH (ldexp, (double, int), scalbn);
+#ifdef __USE_ISOC99
 extern float __REDIRECT_NTH (ldexpf, (float, int), scalbnf);
-#ifdef __MATH_DECLARE_LDOUBLE
+# ifdef __MATH_DECLARE_LDOUBLE
 extern long double __REDIRECT_NTH (ldexpl, (long double, int), scalbnl);
+# endif
 #endif
 
 /* pow.  */
 extern double __REDIRECT_NTH (pow, (double, double), __pow_finite);
+#ifdef __USE_ISOC99
 extern float __REDIRECT_NTH (powf, (float, float), __powf_finite);
-#ifdef __MATH_DECLARE_LDOUBLE
-# ifdef __NO_LONG_DOUBLE_MATH
+# ifdef __MATH_DECLARE_LDOUBLE
+#  ifdef __NO_LONG_DOUBLE_MATH
 extern long double __REDIRECT_NTH (powl, (long double, long double),
 				   __pow_finite);
-# else
+#  else
 extern long double __REDIRECT_NTH (powl, (long double, long double),
 				   __powl_finite);
+#  endif
 # endif
 #endif
 
+#if defined __USE_XOPEN_EXTENDED || defined __USE_ISOC99
 /* remainder.  */
 extern double __REDIRECT_NTH (remainder, (double, double), __remainder_finite);
+#endif
+#ifdef __USE_ISOC99
 extern float __REDIRECT_NTH (remainderf, (float, float), __remainderf_finite);
-#ifdef __MATH_DECLARE_LDOUBLE
-# ifdef __NO_LONG_DOUBLE_MATH
+# ifdef __MATH_DECLARE_LDOUBLE
+#  ifdef __NO_LONG_DOUBLE_MATH
 extern long double __REDIRECT_NTH (remainderl, (long double, long double),
 				   __remainder_finite);
-# else
+#  else
 extern long double __REDIRECT_NTH (remainderl, (long double, long double),
 				   __remainderl_finite);
+#  endif
 # endif
 #endif
 
-#if defined __USE_MISC || defined __USE_XOPEN_EXTENDED
+#if (defined __USE_MISC							\
+     || (defined __USE_XOPEN_EXTENDED && !defined __USE_XOPEN2K8))
 /* scalb.  */
 extern double __REDIRECT_NTH (scalb, (double, double), __scalb_finite);
+#endif
+#if defined __USE_MISC && defined __USE_ISOC99
 extern float __REDIRECT_NTH (scalbf, (float, float), __scalbf_finite);
 # ifdef __MATH_DECLARE_LDOUBLE
 #  ifdef __NO_LONG_DOUBLE_MATH
@@ -404,23 +474,27 @@ extern long double __REDIRECT_NTH (scalbl, (long double, long double),
 
 /* sinh.  */
 extern double __REDIRECT_NTH (sinh, (double), __sinh_finite);
+#ifdef __USE_ISOC99
 extern float __REDIRECT_NTH (sinhf, (float), __sinhf_finite);
-#ifdef __MATH_DECLARE_LDOUBLE
-# ifdef __NO_LONG_DOUBLE_MATH
+# ifdef __MATH_DECLARE_LDOUBLE
+#  ifdef __NO_LONG_DOUBLE_MATH
 extern long double __REDIRECT_NTH (sinhl, (long double), __sinh_finite);
-# else
+#  else
 extern long double __REDIRECT_NTH (sinhl, (long double), __sinhl_finite);
+#  endif
 # endif
 #endif
 
 /* sqrt.  */
 extern double __REDIRECT_NTH (sqrt, (double), __sqrt_finite);
+#ifdef __USE_ISOC99
 extern float __REDIRECT_NTH (sqrtf, (float), __sqrtf_finite);
-#ifdef __MATH_DECLARE_LDOUBLE
-# ifdef __NO_LONG_DOUBLE_MATH
+# ifdef __MATH_DECLARE_LDOUBLE
+#  ifdef __NO_LONG_DOUBLE_MATH
 extern long double __REDIRECT_NTH (sqrtl, (long double), __sqrt_finite);
-# else
+#  else
 extern long double __REDIRECT_NTH (sqrtl, (long double), __sqrtl_finite);
+#  endif
 # endif
 #endif
 

-- 
Joseph S. Myers
joseph@codesourcery.com