diff --git a/.travis.yml b/.travis.yml
index 51999590a93..64ef93f5278 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -5,44 +5,39 @@ sudo: required
 matrix:
   include:
     - os: linux
-      dist: trusty
-      compiler: clang
+      compiler: gcc
       addons:
         apt:
           sources:
             - ubuntu-toolchain-r-test
           packages:
-            # newer g++ version (also pulls libstdc++)
-            - g++-4.9
             - libwww-perl
+            - g++-5
+      before_install:
+        - sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-5 90
+      env: COMPILER=g++-5
     - os: linux
-      dist: trusty
-      compiler: gcc
+      compiler: clang
       addons:
         apt:
           sources:
             - ubuntu-toolchain-r-test
+            - llvm-toolchain-precise-3.7
           packages:
-            # newer g++ version (also pulls libstdc++)
-            - g++-4.9
             - libwww-perl
+            - clang-3.7
       before_install:
-        - sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-4.9 90
-    - os: osx
-      compiler: clang
+        - sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/clang-3.7 90
+      env: COMPILER=clang++-3.7
     - os: osx
       compiler: gcc
-
-addons:
-  apt:
-    packages:
-      - libwww-perl
+      env: COMPILER=g++
+    - os: osx
+      compiler: clang
+      env: COMPILER=clang++
+    - env: NAME="CPP-LINT"
+      script: DIFF=`git diff --name-only master HEAD` && if [ "$DIFF" != "" ]; then python scripts/cpplint.py $DIFF; fi
 
 script:
   - make -C src minisat2-download
-  - make -C src CXXFLAGS="-Wall -O2 -g -Werror -Wno-deprecated-register -pedantic -Wno-sign-compare" -j2 && make -C regression test
-
-matrix:
-  include:
-    - env: NAME="CPP-LINT"
-      script: DIFF=`git diff --name-only master HEAD` && if [ "$DIFF" != "" ]; then python scripts/cpplint.py $DIFF; fi
+  - make -C src CXX=$COMPILER CXXFLAGS="-Wall -O2 -g -Werror -Wno-deprecated-register -pedantic -Wno-sign-compare" -j2 && make -C regression test
diff --git a/src/goto-instrument/unwind.cpp b/src/goto-instrument/unwind.cpp
index 6d33bbe3a11..615cace14c5 100644
--- a/src/goto-instrument/unwind.cpp
+++ b/src/goto-instrument/unwind.cpp
@@ -244,7 +244,7 @@ void goto_unwindt::unwind(
       goto_programt::targett t_goto=goto_program.insert_before(loop_exit);
       unwind_log.insert(t_goto, loop_exit->location_number);
 
-      t_goto->make_goto(get_mutable(goto_program, loop_exit));
+      t_goto->make_goto(goto_program.const_cast_target(loop_exit));
       t_goto->source_location=loop_exit->source_location;
       t_goto->function=loop_exit->function;
       t_goto->guard=true_exprt();
@@ -269,7 +269,8 @@ void goto_unwindt::unwind(
 
     // re-direct any branches that go to loop_head to loop_iter
 
-    for(goto_programt::targett t=get_mutable(goto_program, loop_head);
+    for(goto_programt::targett
+        t=goto_program.const_cast_target(loop_head);
         t!=loop_iter; t++)
     {
       if(!t->is_goto())
diff --git a/src/goto-instrument/unwind.h b/src/goto-instrument/unwind.h
index ec7613e99c1..2e9fbf07f89 100644
--- a/src/goto-instrument/unwind.h
+++ b/src/goto-instrument/unwind.h
@@ -117,13 +117,6 @@ class goto_unwindt
     const goto_programt::const_targett start,
     const goto_programt::const_targett end, // exclusive
     goto_programt &goto_program); // result
-
-  goto_programt::targett get_mutable(
-    goto_programt &goto_program,
-    const goto_programt::const_targett t) const
-  {
-    return goto_program.instructions.erase(t, t);
-  }
 };
 
 #endif // CPROVER_GOTO_INSTRUMENT_UNWIND_H
diff --git a/src/goto-programs/goto_program_template.h b/src/goto-programs/goto_program_template.h
index 4f76eed1be6..d470cd56092 100644
--- a/src/goto-programs/goto_program_template.h
+++ b/src/goto-programs/goto_program_template.h
@@ -248,6 +248,19 @@ class goto_program_templatet
   //! The list of instructions in the goto program
   instructionst instructions;
 
+  // Convert a const_targett to a targett - use with care and avoid
+  // whenever possible
+  targett const_cast_target(const_targett t)
+  {
+    return instructions.erase(t, t);
+  }
+
+  // Dummy for templates with possible const contexts
+  const_targett const_cast_target(const_targett t) const
+  {
+    return t;
+  }
+
   void get_successors(
     targett target,
     targetst &successors);