diff --git a/os/common/startup/ARM/compilers/GCC/rules.mk b/os/common/startup/ARM/compilers/GCC/rules.mk
index f417e4286..a7c78835a 100644
--- a/os/common/startup/ARM/compilers/GCC/rules.mk
+++ b/os/common/startup/ARM/compilers/GCC/rules.mk
@@ -107,12 +107,17 @@ LSTDIR    = $(BUILDDIR)/lst
 
 # Object files groups
 ACOBJS    = $(addprefix $(OBJDIR)/, $(notdir $(ACSRC:.c=.o)))
-ACPPOBJS  = $(addprefix $(OBJDIR)/, $(notdir $(ACPPSRC:.cpp=.o)))
+#ACPPOBJS  = $(addprefix $(OBJDIR)/, $(notdir $(ACPPSRC:.cpp=.o)))
+ACPPOBJS  := $(addprefix $(OBJDIR)/, $(notdir $(patsubst %.cpp, %.o, $(filter %.cpp, $(TCPPSRC)))))
+ACCOBJS   := $(addprefix $(OBJDIR)/, $(notdir $(patsubst %.cc, %.o, $(filter %.cc, $(TCPPSRC)))))
 TCOBJS    = $(addprefix $(OBJDIR)/, $(notdir $(TCSRC:.c=.o)))
-TCPPOBJS  = $(addprefix $(OBJDIR)/, $(notdir $(TCPPSRC:.cpp=.o)))
+#TCPPOBJS  = $(addprefix $(OBJDIR)/, $(notdir $(TCPPSRC:.cpp=.o)))
+TCPPOBJS  := $(addprefix $(OBJDIR)/, $(notdir $(patsubst %.cpp, %.o, $(filter %.cpp, $(TCPPSRC)))))
+TCCOBJS   := $(addprefix $(OBJDIR)/, $(notdir $(patsubst %.cc, %.o, $(filter %.cc, $(TCPPSRC)))))
 ASMOBJS   = $(addprefix $(OBJDIR)/, $(notdir $(ASMSRC:.s=.o)))
 ASMXOBJS  = $(addprefix $(OBJDIR)/, $(notdir $(ASMXSRC:.S=.o)))
-OBJS      = $(ASMXOBJS) $(ASMOBJS) $(ACOBJS) $(TCOBJS) $(ACPPOBJS) $(TCPPOBJS)
+#OBJS      = $(ASMXOBJS) $(ASMOBJS) $(ACOBJS) $(TCOBJS) $(ACPPOBJS) $(TCPPOBJS)
+OBJS      = $(ASMXOBJS) $(ASMOBJS) $(ACOBJS) $(TCOBJS) $(ACPPOBJS) $(ACCOBJS) $(TCPPOBJS) $(TCOBJS)
 
 # Paths
 IINCDIR   = $(patsubst %,-I%,$(INCDIR) $(DINCDIR) $(UINCDIR))
@@ -220,6 +225,24 @@ else
 	@$(CPPC) -c $(CPPFLAGS) $(TOPT) -I. $(IINCDIR) $< -o $@
 endif
 
+$(ACCOBJS) : $(OBJDIR)/%.o : %.cc $(MAKEFILE_LIST)
+ifeq ($(USE_VERBOSE_COMPILE),yes)
+	@echo
+	$(CPPC) -c $(CPPFLAGS) $(AOPT) -I. $(IINCDIR) $< -o $@
+else
+	@echo Compiling $(<F)
+	@$(CPPC) -c $(CPPFLAGS) $(AOPT) -I. $(IINCDIR) $< -o $@
+endif
+
+$(TCCOBJS) : $(OBJDIR)/%.o : %.cc $(MAKEFILE_LIST)
+ifeq ($(USE_VERBOSE_COMPILE),yes)
+	@echo
+	$(CPPC) -c $(CPPFLAGS) $(TOPT) -I. $(IINCDIR) $< -o $@
+else
+	@echo Compiling $(<F)
+	@$(CPPC) -c $(CPPFLAGS) $(TOPT) -I. $(IINCDIR) $< -o $@
+endif
+
 $(ACOBJS) : $(OBJDIR)/%.o : %.c $(MAKEFILE_LIST)
 ifeq ($(USE_VERBOSE_COMPILE),yes)
 	@echo
diff --git a/os/common/startup/ARMCMx/compilers/GCC/mk/rules.mk b/os/common/startup/ARMCMx/compilers/GCC/mk/rules.mk
index c8a6eb7a9..4f7178de5 100644
--- a/os/common/startup/ARMCMx/compilers/GCC/mk/rules.mk
+++ b/os/common/startup/ARMCMx/compilers/GCC/mk/rules.mk
@@ -97,10 +97,13 @@ LSTDIR    := $(BUILDDIR)/lst
 
 # Object files groups
 TCOBJS    := $(addprefix $(OBJDIR)/, $(notdir $(TCSRC:.c=.o)))
-TCPPOBJS  := $(addprefix $(OBJDIR)/, $(notdir $(TCPPSRC:.cpp=.o)))
+#TCPPOBJS  := $(addprefix $(OBJDIR)/, $(notdir $(TCPPSRC:.cpp=.o)))
+TCPPOBJS  := $(addprefix $(OBJDIR)/, $(notdir $(patsubst %.cpp, %.o, $(filter %.cpp, $(TCPPSRC)))))
+TCCOBJS   := $(addprefix $(OBJDIR)/, $(notdir $(patsubst %.cc, %.o, $(filter %.cc, $(TCPPSRC)))))
 ASMOBJS   := $(addprefix $(OBJDIR)/, $(notdir $(ASMSRC:.s=.o)))
 ASMXOBJS  := $(addprefix $(OBJDIR)/, $(notdir $(ASMXSRC:.S=.o)))
-OBJS      := $(ASMXOBJS) $(ASMOBJS) $(ACOBJS) $(TCOBJS) $(ACPPOBJS) $(TCPPOBJS)
+#OBJS      := $(ASMXOBJS) $(ASMOBJS) $(ACOBJS) $(TCOBJS) $(ACPPOBJS) $(TCPPOBJS)
+OBJS      := $(ASMXOBJS) $(ASMOBJS) $(ACOBJS) $(TCOBJS) $(ACPPOBJS) $(TCPPOBJS) $(TCCOBJS)
 
 # Paths
 IINCDIR   := $(patsubst %,-I%,$(INCDIR) $(DINCDIR) $(UINCDIR))
@@ -169,6 +172,15 @@ else
 	@$(CPPC) -c $(CPPFLAGS) -I. $(IINCDIR) $< -o $@
 endif
 
+$(TCCOBJS) : $(OBJDIR)/%.o : %.cc $(MAKEFILE_LIST)
+ifeq ($(USE_VERBOSE_COMPILE),yes)
+	@echo
+	$(CPPC) -c $(CPPFLAGS) -I. $(IINCDIR) $< -o $@
+else
+	@echo Compiling $(<F)
+	@$(CPPC) -c $(CPPFLAGS) -I. $(IINCDIR) $< -o $@
+endif
+
 $(TCOBJS) : $(OBJDIR)/%.o : %.c $(MAKEFILE_LIST)
 ifeq ($(USE_VERBOSE_COMPILE),yes)
 	@echo
diff --git a/os/common/startup/SIMIA32/compilers/GCC/rules.mk b/os/common/startup/SIMIA32/compilers/GCC/rules.mk
index e00560404..73a6d14f8 100644
--- a/os/common/startup/SIMIA32/compilers/GCC/rules.mk
+++ b/os/common/startup/SIMIA32/compilers/GCC/rules.mk
@@ -55,10 +55,13 @@ LSTDIR    = $(BUILDDIR)/lst
 
 # Object files groups
 COBJS     = $(addprefix $(OBJDIR)/, $(notdir $(CSRC:.c=.o)))
-CPPOBJS   = $(addprefix $(OBJDIR)/, $(notdir $(CPPSRC:.cpp=.o)))
+#CPPOBJS   = $(addprefix $(OBJDIR)/, $(notdir $(CPPSRC:.cpp=.o)))
+CPPOBJS  := $(addprefix $(OBJDIR)/, $(notdir $(patsubst %.cpp, %.o, $(filter %.cpp, $(CPPSRC)))))
+CCOBJS   := $(addprefix $(OBJDIR)/, $(notdir $(patsubst %.cc, %.o, $(filter %.cc, $(CPPSRC)))))
 ASMOBJS   = $(addprefix $(OBJDIR)/, $(notdir $(ASMSRC:.s=.o)))
 ASMXOBJS  = $(addprefix $(OBJDIR)/, $(notdir $(ASMXSRC:.S=.o)))
-OBJS      = $(ASMXOBJS) $(ASMOBJS) $(COBJS) $(CPPOBJS)
+#OBJS      = $(ASMXOBJS) $(ASMOBJS) $(COBJS) $(CPPOBJS)
+OBJS      = $(ASMXOBJS) $(ASMOBJS) $(COBJS) $(CPPOBJS) $(CCOBJS)
 
 # Paths
 IINCDIR   = $(patsubst %,-I%,$(INCDIR) $(DINCDIR) $(UINCDIR))
@@ -127,6 +130,15 @@ else
 	@$(CPPC) -c $(CPPFLAGS) -I. $(IINCDIR) $< -o $@
 endif
 
+$(CCOBJS) : $(OBJDIR)/%.o : %.cc $(MAKEFILE_LIST)
+ifeq ($(USE_VERBOSE_COMPILE),yes)
+	@echo
+	$(CPPC) -c $(CPPFLAGS) -I. $(IINCDIR) $< -o $@
+else
+	@echo Compiling $(<F)
+	@$(CPPC) -c $(CPPFLAGS) -I. $(IINCDIR) $< -o $@
+endif
+
 $(COBJS) : $(OBJDIR)/%.o : %.c $(MAKEFILE_LIST)
 ifeq ($(USE_VERBOSE_COMPILE),yes)
 	@echo
diff --git a/readme.txt b/readme.txt
index d3b7ce8be..ed1bc5bc4 100644
--- a/readme.txt
+++ b/readme.txt
@@ -74,6 +74,7 @@
 *****************************************************************************
 
 *** Next ***
+- NEW: Added support for .cc files extensions in makefiles.
 - HAL: New RTCv3 driver for STM32G0xx and STM32G4xx.
 - HAL: Added support for DAC3 and DAC4 in STM32 DACv1 driver.
 - NIL: New functions: chSemResetWithMessageI() and chSemResetWithMessage().