Add makefile for gcc and fix a compile error.

gcc/.gitignore

@@ -0,0 +1,3 @@
+obj/
+well512a_*
+

gcc/Makefile

@@ -0,0 +1,118 @@
+.DEFAULT_GOAL := all
+
+# --- Input variables ---
+BUILD ?= release
+ifeq ($(findstring $(BUILD),debug release),)
+  $(error BUILD must be set to debug or release)
+endif
+
+# Build all executables by default.
+APPS ?= well512a
+
+# If the VERBOSE flag isn't set, then mute superfluous output.
+ifeq ($(VERBOSE),)
+  HUSH_COMPILE = @echo "Compiling $<";
+  HUSH_LINK = @echo "Linking $@";
+  HUSH_GENERATE = @echo "Generating $@";
+  HUSH_CLEAN = @
+endif
+
+# --- Internal variables ---
+ARCH := $(shell uname -p)
+SRC_ROOT := $(abspath ..)
+OUTPUT_DIR := $(SRC_ROOT)/gcc
+INTERMEDIATE_DIR := $(SRC_ROOT)/gcc/obj
+BUILD_DIR := $(INTERMEDIATE_DIR)/$(BUILD)
+
+ARFLAGS = r
+LDFLAGS =
+
+# Always enable debug information.
+CFLAGS += -g
+
+# Flags to generate dependency information.
+CFLAGS += -MD -MP -MT $@
+
+# Predefined flags.
+ifeq ($(BUILD), debug)
+  CFLAGS += -D_DEBUG
+endif
+
+# Enable compiler optimizations for everything except debug.
+# Note that a very aggresssive optimization level is used and it may not be
+# valid for all standard compliant programs. Reduce this level on individual
+# files or modules as needed.
+ifneq ($(BUILD), debug)
+  CFLAGS += -Ofast
+endif
+
+# Flag to turn on extended instruction sets for the compiler.
+CFLAGS += -msse2
+
+# Let C++ inherit all C flags.
+CXXFLAGS = $(CFLAGS)
+
+# --- Internal functions ---
+app_exe = $(OUTPUT_DIR)/$(1)_$(ARCH)_$(BUILD)
+objs_from_src = $(patsubst $(SRC_ROOT)/%, $(BUILD_DIR)/%.o, $(basename $(1)))
+objs_from_src_in = $(call objs_from_src, $(shell find $(1) -name "*.cpp" -o -name "*.c"))
+objs_from_src_in_no_recurse = $(call objs_from_src, $(shell find $(1) -maxdepth 1 -name "*.cpp" -o -name "*.c"))
+
+
+# --- well512a application ---
+ifneq ($(filter well512a,$(APPS)),)
+
+WELL512A_EXE := $(call app_exe,well512a)
+WELL512A_OBJS := $(call objs_from_src_in,$(SRC_ROOT))
+EXES += $(WELL512A_EXE)
+OBJS += $(WELL512A_OBJS)
+
+$(WELL512A_EXE): $(WELL512A_OBJS) $(LIBS)
+
+endif
+
+
+# --- Build rules ---
+
+# Dependencies.
+DEPS = $(OBJS:.o=.d)
+-include $(DEPS)
+
+.PHONY: all clean cleanall help
+
+all: $(EXES)
+
+clean:
+	@echo "Cleaning..."
+	$(HUSH_CLEAN) $(RM) -r $(BUILD_DIR)
+
+cleanall:
+	@echo "Cleaning all..."
+	$(HUSH_CLEAN) $(RM) -r $(INTERMEDIATE_DIR)
+
+help:
+	@echo "BUILD   = Build mode. One of:"
+	@echo "          debug (default)"
+	@echo "          release (optimizations)"
+	@echo "APPS    = Applications to build. Defaults to all."
+	@echo "VERBOSE = Full output from commands if set."
+
+# It's important that libraries are specified last as Ubuntu uses "ld --as-needed" by default.
+# Only the static libraries referenced by the object files will be linked into the executable.
+# Beware that circular dependencies doesn't work with this flag.
+$(EXES):
+	@mkdir -p $(@D)
+	$(HUSH_LINK) $(CXX) -o $@ $^ $(LDFLAGS)
+
+$(BUILD_DIR)/%.a:
+	@mkdir -p $(@D)
+	$(HUSH_GENERATE) $(AR) $(ARFLAGS) $@ $^
+#	$(HUSH_GENERATE) $(AR) $(ARFLAGS) $@ $^ 2> /dev/null
+
+$(BUILD_DIR)/%.o: $(SRC_ROOT)/%.c
+	@mkdir -p $(@D)
+	$(HUSH_COMPILE) $(CC) -c $(CFLAGS) -o $@ $<
+
+$(BUILD_DIR)/%.o: $(SRC_ROOT)/%.cpp
+	@mkdir -p $(@D)
+	$(HUSH_COMPILE) $(CXX) -c $(CXXFLAGS) -o $@ $<

main.cpp

@@ -29,6 +29,7 @@
 #include "RandomWELL512a.h"
 #include "RandomWELL512a_SSE2.h"
 #include "WELL512a.h"
+#include <string.h>     // Needed for memcmp().
 
 void Benchmark()
 {