--- a/build/win32/Makefile.in
+++ b/build/win32/Makefile.in
@@ -59,16 +59,17 @@ USE_STATIC_LIBS = 1
 CPPSRCS = crashinject.cpp
 
 endif # ENABLE_TESTS
 
 include $(topsrcdir)/config/rules.mk
 
 ifndef MOZ_MEMORY
 ifdef WIN32_REDIST_DIR
+ifndef MOZ_DEBUG
 
 ifeq (1400,$(_MSC_VER))
 REDIST_FILES = \
 	Microsoft.VC80.CRT.manifest \
 	msvcm80.dll \
 	msvcp80.dll \
 	msvcr80.dll \
 	$(NULL)
@@ -91,10 +92,11 @@ REDIST_FILES = \
 endif
 
 ifdef REDIST_FILES
 libs::
 	mkdir -p $(FINAL_TARGET)
 	install --preserve-timestamps $(foreach f,$(REDIST_FILES),"$(WIN32_REDIST_DIR)"/$(f)) $(FINAL_TARGET)
 endif
 
+endif # ! MOZ_DEBUG
 endif # WIN32_REDIST_DIR
 endif # ! MOZ_MEMORY

--- a/configure.in
+++ b/configure.in
@@ -7251,17 +7251,17 @@ MOZ_ARG_ENABLE_BOOL(jemalloc,
 
 if test "$NS_TRACE_MALLOC"; then
     MOZ_MEMORY=
 fi
 
 if test -z "$MOZ_MEMORY"; then
   case "${target}" in
     *-mingw*)
-      if test -z "$WIN32_REDIST_DIR"; then
+      if test -z "$WIN32_REDIST_DIR" -a -z "$MOZ_DEBUG"; then
         AC_MSG_WARN([When not building jemalloc, you need to set WIN32_REDIST_DIR to the path to the Visual C++ Redist (usually VCINSTALLDIR\redist\x86\Microsoft.VC80.CRT, for VC++ v8) if you intend to distribute your build.])
       fi
       ;;
   esac
 else
   dnl Don't try to run compiler tests on Windows  
   if test "$OS_ARCH" = "WINNT"; then
     if test -z "$HAVE_64BIT_OS"; then