apply upstream fix for ppc64 infinite loop

R-4.0.0-ppc64-infinite-loop-fix.patch

@@ -0,0 +1,50 @@
+diff -up R-4.0.0/src/main/machar.c.ppc64 R-4.0.0/src/main/machar.c
+--- R-4.0.0/src/main/machar.c.ppc64	2020-06-02 14:42:18.741222048 -0400
++++ R-4.0.0/src/main/machar.c	2020-06-02 14:44:26.523106368 -0400
+@@ -98,21 +98,22 @@ MACH_NAME(int *ibeta, int *it, int *irnd
+ {
+ 	volatile DTYPE a, b, beta, betain, betah, one,
+ 		t, temp, tempa, temp1, two, y, z, zero;
+-	int i, itemp, iz, j, k, mx, nxres;
++	int i, iz, j, k, mx, nxres;
+ 
+ 	one = 1;
+ 	two = one+one;
+ 	zero = one-one;
+ 
+ 		/* determine ibeta, beta ala malcolm. */
+-
+-	a = one;
++	a = one; // a = <large> = 9.0072e+15 for 'double' is used later
+ 	do {
+ 		a = a + a;
+ 		temp = a + one;
+ 		temp1 = temp - a;
+ 	}
+ 	while(temp1 - one == zero);
++#ifdef _no_longer___did_overflow_ // on IBM PowerPPC ('Power 8')
++	int itemp;
+ 	b = one;
+ 	do {
+ 		b = b + b;
+@@ -121,6 +122,9 @@ MACH_NAME(int *ibeta, int *it, int *irnd
+ 	}
+ 	while (itemp == 0);
+ 	*ibeta = itemp;
++#else
++	*ibeta = (int) FLT_RADIX;
++#endif
+ 	beta = *ibeta;
+ 
+ 		/* determine it, irnd */
+diff -up R-4.0.0/src/main/platform.c.ppc64 R-4.0.0/src/main/platform.c
+--- R-4.0.0/src/main/platform.c.ppc64	2020-06-02 14:44:40.940754817 -0400
++++ R-4.0.0/src/main/platform.c	2020-06-02 14:45:08.940072121 -0400
+@@ -43,6 +43,7 @@
+ #include <Rinterface.h>
+ #include <Fileio.h>
+ #include <ctype.h>			/* toupper */
++#include <float.h> // -> FLT_RADIX
+ #include <limits.h>
+ #include <string.h>
+ #include <stdlib.h>			/* for realpath */

R.spec

@@ -152,7 +152,7 @@
 
 Name: R
 Version: %{major_version}.%{minor_version}.%{patch_version}
-Release: 1%{?dist}
+Release: 2%{?dist}
 Summary: A language for data analysis and graphics
 URL: http://www.r-project.org
 Source0: https://cran.r-project.org/src/base/R-4/R-%{version}.tar.gz
@@ -200,6 +200,8 @@ BuildRequires: stunnel
 %endif
 # see https://bugzilla.redhat.com/show_bug.cgi?id=1324145
 Patch1: R-3.3.0-fix-java_path-in-javareconf.patch
+# https://github.com/wch/r-source/commit/6857d53313bf7a5afea4e3f0142d69a069b701d0
+Patch2: R-4.0.0-ppc64-infinite-loop-fix.patch
 License: GPLv2+
 BuildRequires: gcc-gfortran
 BuildRequires: gcc-c++, tex(latex), texinfo-tex
@@ -517,6 +519,7 @@ from the R project.  This package provides the static libRmath library.
 %setup -q -n %{name}-%{version}
 %endif
 %patch1 -p1 -b .fixpath
+%patch2 -p1 -b .ppc64
 
 # Filter false positive provides.
 cat <<EOF > %{name}-prov
@@ -1243,6 +1246,9 @@ R CMD javareconf \
 %{_libdir}/libRmath.a
 
 %changelog
+* Tue Jun 2 2020 Tom Callaway <spot@fedoraproject.org> - 4.0.0-2
+- apply upstream fix for ppc64 infinite loop
+
 * Fri May 8 2020 Tom Callaway <spot@fedoraproject.org> - 4.0.0-1
 - update to 4.0.0
   NOTE: This major release update requires all installed R modules to be rebuilt in order to work.