diff --git a/flang/include/flang/Evaluate/integer.h b/flang/include/flang/Evaluate/integer.h
index 7395645701265..b62e2bcb90f2f 100644
--- a/flang/include/flang/Evaluate/integer.h
+++ b/flang/include/flang/Evaluate/integer.h
@@ -27,7 +27,7 @@
 #include <string>
 #include <type_traits>
 
-// Some environments, viz. glibc 2.17, allow the macro HUGE
+// Some environments, viz. glibc 2.17 and *BSD, allow the macro HUGE
 // to leak out of <math.h>.
 #undef HUGE
 
diff --git a/flang/include/flang/Evaluate/real.h b/flang/include/flang/Evaluate/real.h
index b7af0ff6b431c..6f2466c9da677 100644
--- a/flang/include/flang/Evaluate/real.h
+++ b/flang/include/flang/Evaluate/real.h
@@ -18,7 +18,7 @@
 #include <limits>
 #include <string>
 
-// Some environments, viz. glibc 2.17, allow the macro HUGE
+// Some environments, viz. glibc 2.17 and *BSD, allow the macro HUGE
 // to leak out of <math.h>.
 #undef HUGE
 
diff --git a/flang/lib/Decimal/decimal-to-binary.cpp b/flang/lib/Decimal/decimal-to-binary.cpp
index eebd0736b67ad..94c5177423739 100644
--- a/flang/lib/Decimal/decimal-to-binary.cpp
+++ b/flang/lib/Decimal/decimal-to-binary.cpp
@@ -16,6 +16,10 @@
 #include <cstring>
 #include <utility>
 
+// Some environments, viz. glibc 2.17 and *BSD, allow the macro HUGE
+// to leak out of <math.h>.
+#undef HUGE
+
 namespace Fortran::decimal {
 
 template <int PREC, int LOG10RADIX>
diff --git a/flang/lib/Evaluate/fold-implementation.h b/flang/lib/Evaluate/fold-implementation.h
index 470dbe9e74099..34f79f9e6f25b 100644
--- a/flang/lib/Evaluate/fold-implementation.h
+++ b/flang/lib/Evaluate/fold-implementation.h
@@ -39,7 +39,7 @@
 #include <type_traits>
 #include <variant>
 
-// Some environments, viz. glibc 2.17, allow the macro HUGE
+// Some environments, viz. glibc 2.17 and *BSD, allow the macro HUGE
 // to leak out of <math.h>.
 #undef HUGE