diff --git a/src/cmd/ksh93/Mamfile b/src/cmd/ksh93/Mamfile
index cb560713a..9f3174377 100644
--- a/src/cmd/ksh93/Mamfile
+++ b/src/cmd/ksh93/Mamfile
@@ -1216,6 +1216,7 @@ make install
 						exec - iffe ${IFFEFLAGS} -v -c "${CC} ${mam_cc_FLAGS} ${KSH_RELFLAGS} ${KSH_SHOPTFLAGS} ${CCFLAGS} ${LDFLAGS}" ref ${mam_cc_L+-L.} ${mam_cc_L+-L${INSTALLROOT}/lib} -I${PACKAGE_ast_INCLUDE} -I${INSTALLROOT}/include ${mam_libdll} ${mam_libcmd} ${mam_libast} ${mam_libm} ${mam_libnsl} : run features/math.sh ${PACKAGEROOT}/src/cmd/ksh93/data/math.tab
 						make ${PACKAGE_ast_INCLUDE}/ast_standards.h implicit
 						done ${PACKAGE_ast_INCLUDE}/ast_standards.h dontcare
+						prev ${INSTALLROOT}/src/lib/libast/FEATURE/float implicit
 					done FEATURE/math generated
 					prev include/streval.h implicit
 					prev FEATURE/options implicit
diff --git a/src/lib/libast/Mamfile b/src/lib/libast/Mamfile
index af0f66caa..0ce5ca321 100644
--- a/src/lib/libast/Mamfile
+++ b/src/lib/libast/Mamfile
@@ -3128,6 +3128,7 @@ make install
 					prev include/tm.h implicit
 					prev include/error.h implicit
 					prev include/ast.h implicit
+					prev FEATURE/float implicit
 				done comp/omitted.c
 				meta omitted.o %.c>%.o comp/omitted.c omitted
 				prev comp/omitted.c
diff --git a/src/lib/libast/comp/omitted.c b/src/lib/libast/comp/omitted.c
index 16d2db655..247aa52bf 100644
--- a/src/lib/libast/comp/omitted.c
+++ b/src/lib/libast/comp/omitted.c
@@ -15,6 +15,7 @@ __STDPP__directive pragma pp:hide utime utimes
 #include <error.h>
 #include <tm.h>
 
+#include "FEATURE/float"
 #include "FEATURE/omitted"
 
 #undef	OMITTED
@@ -1145,6 +1146,36 @@ __EXPORT__ double (*_imp__strtod)(const char*, char**) = strtod;
 
 #endif
 
+/* Kludge to deal with GCC's overzealous optimizer breaking the pow functions.
+ *
+ * Removal of this will break IEEE floating point on the SVR4 platforms.
+ */
+#if _need_ast_pow_funs
+# if _lib_powf
+float (*volatile _ast_ppowf)(float,float) = &powf;
+float _ast_powf(float x, float y)
+{
+	return x == 1.0F ? 1.0F : (*_ast_ppowf)(x,y);
+}
+# endif
+
+# if _lib_pow
+double (*volatile _ast_ppow)(double,double) = &pow;
+double _ast_pow(double x, double y)
+{
+	return x == 1.0 ? 1.0 : (*_ast_ppow)(x,y);
+}
+# endif
+
+# if _lib_powl
+long double (*volatile _ast_ppowl)(long double,long double) = &powl;
+long double _ast_powl(long double x, long double y)
+{
+	return x == 1.0L ? 1.0L : (*_ast_ppowl)(x,y);
+}
+# endif
+#endif
+
 #ifndef OMITTED
 
 NoN(omitted)
diff --git a/src/lib/libast/features/float b/src/lib/libast/features/float
index 0a65200e7..44ff12f92 100644
--- a/src/lib/libast/features/float
+++ b/src/lib/libast/features/float
@@ -2,7 +2,7 @@ set	prototyped
 set	nooptimize
 set	stdio FEATURE/standards
 hdr	float,limits,math,values
-lib,npt	frexp,frexpl,ldexp,ldexpl,finite,finitel,isinfl,isnanl,copysign,copysignl FEATURE/standards math.h -lm
+lib,npt	frexp,frexpl,ldexp,ldexpl,finite,finitel,isinfl,isnanl,copysign,copysignl,powf,pow,powl FEATURE/standards math.h -lm
 lib	fpclassify -lm note{ fpclassify present and works }end link{
 		#include <sys/types.h>
 		#include <sys/stat.h>
@@ -1231,15 +1231,33 @@ tst	- -DSCAN=1 - -lm -DSTRTO=1 - -DMAC=1 - -DDIV=1 - -DEXP=1 - -DADD=1 - -DMPY=1
 	}
 }end
 
-tst	ast_pow_ieee -lm note{ pow(1,inf) is IEEE compliant }end execute{
+if	need_ast_pow_macros -lm note{ are IEEE pow macro replacements needed }end execute{
 	#include <sys/types.h>
 	#include <sys/stat.h>
 	#include <stdlib.h>
 	#include <unistd.h>
 	#include <math.h>
-	int main() { return pow(1.0, 1.0 / 0.0) != 1.0; }
-}end fail{
-	echo '#define powf(x,y)	(((x)==1.0)?1.0:powf((x),(y)))'
-	echo '#define pow(x,y)	(((x)==1.0)?1.0:pow((x),(y)))'
-	echo '#define powl(x,y)	(((x)==1.0)?1.0:powl((x),(y)))'
-}end
+	int main() { return pow(1.0, 1.0 / 0.0) == 1.0; }
+}end {
+	#define powf(x,y)	(((x)==1.0)?1.0:powf((x),(y)))
+	#define pow(x,y)	(((x)==1.0)?1.0:pow((x),(y)))
+	#define powl(x,y)	(((x)==1.0)?1.0:powl((x),(y)))
+}
+elif	tst need_ast_pow_funs -lm note{ are IEEE pow function replacements needed }end execute{
+	#include <sys/types.h>
+	#include <sys/stat.h>
+	#include <stdlib.h>
+	#include <unistd.h>
+	#include <math.h>
+	/* This bit of obfuscation defeats GCC's code optimizer. */
+	double (*volatile _ast_ppow)(double,double);
+	int main () { _ast_ppow = &pow; return (*_ast_ppow)(1.0, 1.0 / 0.0) == 1.0; }
+}end {
+	float			_ast_powf(float x, float y);
+	double			_ast_pow(double x, double y);
+	long double		_ast_powl(long double x, long double y);
+	#define powf(x,y)	(_ast_powf((x),(y)))
+	#define pow(x,y)	(_ast_pow((x),(y)))
+	#define powl(x,y)	(_ast_powl((x),(y)))
+}
+endif