Why is this happening?

WTF.c

/*
gcc -o plugins/Sapphire/primitives.os -c -std=c11 -Werror=return-type -Wno-unused-local-typedefs -Wall -Wno-pointer-arith -mtune=native -msse2 -flto -O2 -funroll-loops -Wcast-align -pg -g -DUSE_AMDLIBM -DHAS_ATOMIC -DHAS_THREAD -DHAS_MUTEX -DHAS_PTHREAD -fPIC -DUSE_INTEL_TBB plugins/Sapphire/primitives.c
In file included from plugins/Sapphire/primitives.h:20:0,
                 from plugins/Sapphire/primitives.c:1:
plugins/Sapphire/primitive_types.h:8:8: error: expected identifier or '(' before string constant
 extern "C" {

*/
//THe File:

#ifndef SAPPHIRE_UNCLE_TUPELO_HEAD
#define SAPPHIRE_UNCLE_TUPELO_HEAD

/////
// Primitives header
//
// Defines Hard-Coded and optimized primitives.
//
// All Sphere 1.6 primitives are formed of some combination of these
//   primitives and a certain amount of JS.
//
// The functions in the FJ-GL header are only to be called directly
//   synchronously with scripts.
//
// These are immediate calls. They must be called from the drawing thread.
//

#include <stdint.h>

#include "primitive_types.h"

#ifndef __cplusplus

#include <stdbool.h>

#endif

#ifdef __cplusplus

extern "C" {

#endif

void InitPrimitives(uint32_t ID);


void TS_BezierCurve(int *x, int *y, bool cubic, unsigned int step, uint32_t color);
void TS_BezierCurve_arg(struct BezierCurve_arg *arg)

void TS_GradientComplex(int x, int y, unsigned int w, unsigned int h, unsigned int radius, uint32_t color[2]);
void TS_GradientComplex_arg(struct Complex_arg *arg);

void TS_GradientLine(int x[2], int y[2], uint32_t color[2]);
void TS_GradientLine_arg(struct Line_arg *arg);

void TS_OutlinedEllipse(int x, int y, unsigned int hradius, unsigned int vradius, float angle, uint32_t color);
void TS_OutlinedEllipse_arg(struct Ellipse_arg *arg);

void TS_GradientEllipse(int x, int y, unsigned int hradius, unsigned int vradius, float angle, uint32_t color[2]);
void TS_GradientEllipse_arg(struct Ellipse_arg *arg);

void TS_GradientRectangle(int x, int y, unsigned int w, unsigned int h, uint32_t color[4]);
void TS_GradientRectangle_arg(struct Rectangle_arg *arg);

void TS_GradientTriangle(int x[3], int y[3], uint32_t color[3]);
void TS_GradientTriangle_arg(struct Triangle_arg *arg);

void TS_Point(int x, int y, uint32_t color);
void TS_Point_arg(struct Point_arg *arg);

#ifdef __cplusplus

}

#endif

#endif