From ab7169da5a6771f103fa0b1f448f0a17b1dfd92c Mon Sep 17 00:00:00 2001
From: michellepistner <pistner@psu.edu>
Date: Fri, 31 May 2024 12:34:17 -0400
Subject: [PATCH] updating configures

---
 configure    | 13 +++++++++++++
 configure.ac | 16 ++++++++++++++++
 2 files changed, 29 insertions(+)

diff --git a/configure b/configure
index ec25cdb..46829a2 100755
--- a/configure
+++ b/configure
@@ -3252,6 +3252,19 @@ cd "${BUILDDIR}"
 # MPN: These updates were from a (very, very useful) help question posted to r-package-devel
 # Credit goes to Ivan Krylov.
 
+cat > test-omp.cpp <<EOF
+#include <omp.h>
+extern "C" void configtest(int * arg) {
+  *arg = omp_get_num_threads();
+}
+EOF
+# Without the following you're relying on the GNU/Linux-like behaviour
+# w.r.t. undefined symbols (see WRE 1.2.1.1):
+cat > Makevars <<EOF
+PKG_CXXFLAGS = \$(SHLIB_OPENMP_CXXFLAGS)
+PKG_LIBS = \$(SHLIB_OPENMP_CXXFLAGS)
+EOF
+
 # compile and link the shared object
 "${R_HOME}/bin/R" CMD SHLIB test-omp.cpp
 # load it and use a function from the inside
diff --git a/configure.ac b/configure.ac
index 2ee601c..ca56a82 100644
--- a/configure.ac
+++ b/configure.ac
@@ -46,6 +46,22 @@ mkdir -p "${BUILDDIR}"
 owd=$(pwd)
 cd "${BUILDDIR}"
 
+# MPN: These updates were from a (very, very useful) help question posted to r-package-devel
+# Credit goes to Ivan Krylov.
+
+cat > test-omp.cpp <<EOF
+#include <omp.h>
+extern "C" void configtest(int * arg) {
+  *arg = omp_get_num_threads();
+}
+EOF
+# Without the following you're relying on the GNU/Linux-like behaviour
+# w.r.t. undefined symbols (see WRE 1.2.1.1):
+cat > Makevars <<EOF
+PKG_CXXFLAGS = \$(SHLIB_OPENMP_CXXFLAGS)
+PKG_LIBS = \$(SHLIB_OPENMP_CXXFLAGS)
+EOF
+
 # compile and link the shared object
 "${R_HOME}/bin/R" CMD SHLIB test-omp.cpp
 # load it and use a function from the inside