diff --git a/src/backend/utils/adt/float.c b/src/backend/utils/adt/float.c
index c7c0b58..a95ebe5 100644
*** a/src/backend/utils/adt/float.c
--- b/src/backend/utils/adt/float.c
*************** static float8 atan_1_0 = 0;
*** 77,91 ****
  static float8 tan_45 = 0;
  static float8 cot_45 = 0;
  
  /* Local function prototypes */
  static int	float4_cmp_internal(float4 a, float4 b);
  static int	float8_cmp_internal(float8 a, float8 b);
  static double sind_q1(double x);
  static double cosd_q1(double x);
! 
! /* This is INTENTIONALLY NOT STATIC.  Don't "fix" it. */
! void init_degree_constants(float8 thirty, float8 forty_five, float8 sixty,
! 					  float8 one_half, float8 one);
  
  #ifndef HAVE_CBRT
  /*
--- 77,100 ----
  static float8 tan_45 = 0;
  static float8 cot_45 = 0;
  
+ /*
+  * These are intentionally not static; don't "fix" them.  They will never
+  * be referenced by other files, much less changed; but we don't want the
+  * compiler to know that, else it might try to precompute expressions
+  * involving them.  See comments for init_degree_constants().
+  */
+ float8		degree_c_thirty = 30.0;
+ float8		degree_c_forty_five = 45.0;
+ float8		degree_c_sixty = 60.0;
+ float8		degree_c_one_half = 0.5;
+ float8		degree_c_one = 1.0;
+ 
  /* Local function prototypes */
  static int	float4_cmp_internal(float4 a, float4 b);
  static int	float8_cmp_internal(float8 a, float8 b);
  static double sind_q1(double x);
  static double cosd_q1(double x);
! static void init_degree_constants(void);
  
  #ifndef HAVE_CBRT
  /*
*************** dtan(PG_FUNCTION_ARGS)
*** 1814,1848 ****
   * compilers out there that will precompute expressions such as sin(constant)
   * using a sin() function different from what will be used at runtime.  If we
   * want exact results, we must ensure that none of the scaling constants used
!  * in the degree-based trig functions are computed that way.
!  *
!  * The whole approach fails if init_degree_constants() gets inlined into the
!  * call sites, since then constant-folding can happen anyway.  Currently it
!  * seems sufficient to declare it non-static to prevent that.  We have no
!  * expectation that other files will call this, but don't tell gcc that.
   *
   * Other hazards we are trying to forestall with this kluge include the
   * possibility that compilers will rearrange the expressions, or compute
   * some intermediate results in registers wider than a standard double.
   */
! void
! init_degree_constants(float8 thirty, float8 forty_five, float8 sixty,
! 					  float8 one_half, float8 one)
  {
! 	sin_30 = sin(thirty * RADIANS_PER_DEGREE);
! 	one_minus_cos_60 = 1.0 - cos(sixty * RADIANS_PER_DEGREE);
! 	asin_0_5 = asin(one_half);
! 	acos_0_5 = acos(one_half);
! 	atan_1_0 = atan(one);
! 	tan_45 = sind_q1(forty_five) / cosd_q1(forty_five);
! 	cot_45 = cosd_q1(forty_five) / sind_q1(forty_five);
  	degree_consts_set = true;
  }
  
  #define INIT_DEGREE_CONSTANTS() \
  do { \
  	if (!degree_consts_set) \
! 		init_degree_constants(30.0, 45.0, 60.0, 0.5, 1.0); \
  } while(0)
  
  
--- 1823,1853 ----
   * compilers out there that will precompute expressions such as sin(constant)
   * using a sin() function different from what will be used at runtime.  If we
   * want exact results, we must ensure that none of the scaling constants used
!  * in the degree-based trig functions are computed that way.  To do so, we
!  * compute them from the variables degree_c_thirty etc, which are also really
!  * constants, but the compiler cannot assume that.
   *
   * Other hazards we are trying to forestall with this kluge include the
   * possibility that compilers will rearrange the expressions, or compute
   * some intermediate results in registers wider than a standard double.
   */
! static void
! init_degree_constants(void)
  {
! 	sin_30 = sin(degree_c_thirty * RADIANS_PER_DEGREE);
! 	one_minus_cos_60 = 1.0 - cos(degree_c_sixty * RADIANS_PER_DEGREE);
! 	asin_0_5 = asin(degree_c_one_half);
! 	acos_0_5 = acos(degree_c_one_half);
! 	atan_1_0 = atan(degree_c_one);
! 	tan_45 = sind_q1(degree_c_forty_five) / cosd_q1(degree_c_forty_five);
! 	cot_45 = cosd_q1(degree_c_forty_five) / sind_q1(degree_c_forty_five);
  	degree_consts_set = true;
  }
  
  #define INIT_DEGREE_CONSTANTS() \
  do { \
  	if (!degree_consts_set) \
! 		init_degree_constants(); \
  } while(0)