iperf3: fix build with autoconf 2.71

Add patch that checks for CPP prog, which helps to resolve build
errors:

../git/configure: line 14427: CPP: command not found
| ../git/configure: line 14553: ac_fn_c_try_cpp: command not found
| ../git/configure: line 14553: ac_fn_c_try_cpp: command not found

Signed-off-by: Andrey Zhizhikin <andrey.z@gmail.com>
Signed-off-by: Khem Raj <raj.khem@gmail.com>

2 files changed, 32 insertions, 0 deletions

diff --git a/meta-oe/recipes-benchmark/iperf3/iperf3/0001-configure.ac-check-for-CPP-prog.patch b/meta-oe/recipes-benchmark/iperf3/iperf3/0001-configure.ac-check-for-CPP-prog.patch
new file mode 100644
index 000000000..739fd20fc
--- /dev/null
+++ b/meta-oe/recipes-benchmark/iperf3/iperf3/0001-configure.ac-check-for-CPP-prog.patch
@@ -0,0 +1,31 @@
+From cc4499cd4cfcb655fc44c3f3571eee20663dafde Mon Sep 17 00:00:00 2001
+From: Andrey Zhizhikin <andrey.z@gmail.com>
+Date: Wed, 3 Feb 2021 20:44:34 +0000
+Subject: [PATCH] configure.ac: check for CPP prog
+
+Absence of check for CPP_PROG causes following build errors:
+| checking TCP_CONGESTION socket option... ../git/configure: line 14427: CPP: command not found
+| ../git/configure: line 14553: ac_fn_c_try_cpp: command not found
+| ../git/configure: line 14553: ac_fn_c_try_cpp: command not found
+
+Upstream-Status: Pending
+Signed-off-by: Andrey Zhizhikin <andrey.z@gmail.com>
+---
+ configure.ac | 1 +
+ 1 file changed, 1 insertion(+)
+
+diff --git a/configure.ac b/configure.ac
+index 939cf0a..f75b398 100644
+--- a/configure.ac
++++ b/configure.ac
+@@ -47,6 +47,7 @@ AC_CANONICAL_HOST
+ # Checks for tools: c compiler, ranlib (used for creating static libraries),
+ # symlinks and libtool
+ AC_PROG_CC
++AC_PROG_CPP
+ AC_PROG_RANLIB
+ AC_PROG_LN_S
+ AC_PROG_LIBTOOL
+-- 
+2.17.1
+
diff --git a/meta-oe/recipes-benchmark/iperf3/iperf3_3.9.bb b/meta-oe/recipes-benchmark/iperf3/iperf3_3.9.bb
index d969555c2..be75837be 100644
--- a/meta-oe/recipes-benchmark/iperf3/iperf3_3.9.bb
+++ b/meta-oe/recipes-benchmark/iperf3/iperf3_3.9.bb
@@ -13,6 +13,7 @@ LIC_FILES_CHKSUM = "file://LICENSE;md5=b7fb682e9941a49f1214dcd7441410d7"
 
 SRC_URI = "git://github.com/esnet/iperf.git \
            file://0002-Remove-pg-from-profile_CFLAGS.patch \
+           file://0001-configure.ac-check-for-CPP-prog.patch \
            "
 
 SRCREV = "1f8fb13297f3e3e40169ebcd12e171167e394473"