diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 9062067bcf..2c4f96e55d 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,7 @@
+2017-06-17  Simon Marchi  <simon.marchi@ericsson.com>
+
+	* Makefile.in (COMPILE.pre): Add "-x c++".
+
 2017-06-16  Alan Hayward  <alan.hayward@arm.com>
 	    Pedro Alves  <palves@redhat.com>
 	    Yao Qi  <yao.qi@linaro.org>
diff --git a/gdb/Makefile.in b/gdb/Makefile.in
index 5e5fcaae7a..153a5dd6fb 100644
--- a/gdb/Makefile.in
+++ b/gdb/Makefile.in
@@ -114,7 +114,7 @@ depcomp = $(SHELL) $(srcdir)/../depcomp
 
 # Note that these are overridden by GNU make-specific code below if
 # GNU make is used.  The overrides implement dependency tracking.
-COMPILE.pre = $(CXX) $(CXX_DIALECT)
+COMPILE.pre = $(CXX) -x c++ $(CXX_DIALECT)
 COMPILE.post = -c -o $@
 COMPILE = $(COMPILE.pre) $(INTERNAL_CFLAGS) $(COMPILE.post)
 POSTCOMPILE = @true
diff --git a/gdb/gdbserver/ChangeLog b/gdb/gdbserver/ChangeLog
index 80240ffe38..eef680cb34 100644
--- a/gdb/gdbserver/ChangeLog
+++ b/gdb/gdbserver/ChangeLog
@@ -1,3 +1,7 @@
+2017-06-17  Simon Marchi  <simon.marchi@ericsson.com>
+
+	* Makefile.in (COMPILE.pre): Add "-x c++".
+
 2017-06-09  Sergio Durigan Junior  <sergiodj@redhat.com>
 
 	* fork-child.c: Conditionally include <signal.h>.
diff --git a/gdb/gdbserver/Makefile.in b/gdb/gdbserver/Makefile.in
index 834425dc44..4a031e165a 100644
--- a/gdb/gdbserver/Makefile.in
+++ b/gdb/gdbserver/Makefile.in
@@ -65,7 +65,7 @@ depcomp = $(SHELL) $(srcdir)/../depcomp
 
 # Note that these are overridden by GNU make-specific code below if
 # GNU make is used.  The overrides implement dependency tracking.
-COMPILE.pre = $(CXX) $(CXX_DIALECT)
+COMPILE.pre = $(CXX) -x c++ $(CXX_DIALECT)
 COMPILE.post = -c -o $@
 COMPILE = $(COMPILE.pre) $(INTERNAL_CFLAGS) $(COMPILE.post)
 POSTCOMPILE = @true