More compat work. Rename libraries from LibFoo.a => libfoo.a

This makes it more straightforward to build a cross-compiler toolchain.
Also move math stuff from LibC to LibM.

LibM/.gitignore

@@ -0,0 +1,3 @@
+*.o
+*.d
+libm.a

LibM/Makefile

@@ -0,0 +1,32 @@
+OBJS = math.o
+
+LIBRARY = libm.a
+STANDARD_FLAGS = -std=c++17
+WARNING_FLAGS = -Wextra -Wall -Wundef -Wcast-qual -Wwrite-strings -Wimplicit-fallthrough
+FLAVOR_FLAGS = -fno-exceptions -fno-rtti
+OPTIMIZATION_FLAGS = -Os
+INCLUDE_FLAGS = -I.. -I.
+
+DEFINES = -DSERENITY -DUSERLAND -DSANITIZE_PTRS
+
+CXXFLAGS = -MMD -MP $(WARNING_FLAGS) $(OPTIMIZATION_FLAGS) $(FLAVOR_FLAGS) $(STANDARD_FLAGS) $(INCLUDE_FLAGS) $(DEFINES)
+CXX = i686-pc-serenity-g++
+LD = i686-pc-serenity-ld
+AR = i686-pc-serenity-ar
+
+all: $(LIBRARY)
+
+$(LIBRARY): $(OBJS)
+	@echo "LIB $@"; $(AR) rcs $@ $(OBJS)
+
+.cpp.o:
+	@echo "CXX $<"; $(CXX) $(CXXFLAGS) -o $@ -c $<
+
+%.no: %.asm
+	@echo "NASM $@"; nasm -f elf -o $@ $<
+
+-include $(OBJS:%.o=%.d)
+
+clean:
+	@echo "CLEAN"; rm -f $(LIBRARY) $(OBJS) *.d
+

LibM/install.sh

@@ -0,0 +1,6 @@
+#!/bin/bash
+
+mkdir -p ../Root/usr/include/sys/
+mkdir -p ../Root/usr/lib/
+cp *.h ../Root/usr/include/
+cp libm.a ../Root/usr/lib/

LibM/math.cpp

@@ -0,0 +1,23 @@
+#include <LibC/assert.h>
+#include <LibM/math.h>
+
+extern "C" {
+
+double cos(double)
+{
+    assert(false);
+}
+
+double sin(double)
+{
+    assert(false);
+}
+
+double pow(double x, double y)
+{
+    (void)x;
+    (void)y;
+    assert(false);
+}
+
+}

LibM/math.h

@@ -0,0 +1,57 @@
+#pragma once
+
+#include <sys/cdefs.h>
+
+__BEGIN_DECLS
+
+#define HUGE_VAL 1e10000
+
+double acos(double);
+float acosf(float);
+double asin(double);
+float asinf(float);
+double atan(double);
+float atanf(float);
+double atan2(double, double);
+float atan2f(float, float);
+double cos(double);
+float cosf(float);
+double cosh(double);
+float coshf(float);
+double sin(double);
+float sinf(float);
+double sinh(double);
+float sinhf(float);
+double tan(double);
+float tanf(float);
+double tanh(double);
+float tanhf(float);
+double ceil(double);
+float ceilf(float);
+double floor(double);
+float floorf(float);
+double round(double);
+float roundf(float);
+double fabs(double);
+float fabsf(float);
+double fmod(double, double);
+float fmodf(float, float);
+double exp(double);
+float expf(float);
+double frexp(double, int* exp);
+float frexpf(float, int* exp);
+double log(double);
+float logf(float);
+double log10(double);
+float log10f(float);
+double sqrt(double);
+float sqrtf(float);
+double modf(double, double*);
+float modff(float, float*);
+double ldexp(double, int exp);
+float ldexpf(float, int exp);
+
+double pow(double x, double y);
+
+__END_DECLS
+