diff --git a/icu4c/source/common/listformatter.cpp b/icu4c/source/common/listformatter.cpp
index a0ab80a4905..d105654755f 100644
--- a/icu4c/source/common/listformatter.cpp
+++ b/icu4c/source/common/listformatter.cpp
@@ -170,9 +170,16 @@ enum {
 
 struct ListFormatter::ListPatternsSink : public ResourceSink {
     UnicodeString two, start, middle, end;
+#if ((U_PLATFORM == U_PF_AIX) || (U_PLATFORM == U_PF_OS390)) && (U_CPLUSPLUS_VERSION < 11)
+    char aliasedStyle[kStyleLenMax+1];
+    ListPatternsSink() {
+      uprv_memset(aliasedStyle, 0, kStyleLenMax+1);
+    }
+#else
     char aliasedStyle[kStyleLenMax+1] = {0};
 
     ListPatternsSink() {}
+#endif
     virtual ~ListPatternsSink();
 
     void setAliasedStyle(UnicodeString alias) {
diff --git a/icu4c/source/config/make2sh.sed b/icu4c/source/config/make2sh.sed
index df53e4e520c..783e6a199e8 100644
--- a/icu4c/source/config/make2sh.sed
+++ b/icu4c/source/config/make2sh.sed
@@ -4,6 +4,7 @@
 s%^\([a-zA-Z0-9\._-]*\)[ 	]*+=%\1=$(\1) %
 s%^[A-Z]*_SO_TARG*%## &%
 s%^SHARED_OBJECT.*%## &%
+s%^_%.*%## &%
 s%^LD_SONAME.*%## &%
 s%$(\([^\)]*\))%${\1}%g
 s%^	%#M#	%