diff --git a/icu4c/source/config/mh-solaris b/icu4c/source/config/mh-solaris
index 5e2abcfeb59..a26b468d878 100644
--- a/icu4c/source/config/mh-solaris
+++ b/icu4c/source/config/mh-solaris
@@ -15,8 +15,8 @@ SHAREDLIBCXXFLAGS = -KPIC
 SHAREDLIBCPPFLAGS = -DPIC
 
 ## Commands to generate dependency files
-GEN_DEPS.c=  $(CC) -xM $(DEFS) $(CPPFLAGS)
-GEN_DEPS.cc= $(CXX) -xM $(DEFS) $(CPPFLAGS)
+GEN_DEPS.c=  $(CC) -xM $(DEFS) $(CPPFLAGS) $(CFLAGS)
+GEN_DEPS.cc= $(CXX) -xM $(DEFS) $(CPPFLAGS) $(CXXFLAGS)
 
 ifeq ($(UCLN_NO_AUTO_CLEANUP),0)
 # set up init point.