trying to fix C++ build

src/cones.c

@@ -39,13 +39,6 @@ void BLAS(scal)(const blas_int *n, const scs_float *sa, scs_float *sx,
 }
 #endif
 
-#endif
-
-/* Forward declare exponential cone projection routine.
- * Implemented in exp_cone.c.
- */
-scs_float SCS(proj_pd_exp_cone)(scs_float *v0, scs_int primal);
-
 // Forward declare spectral matrix cone projections
 scs_int SCS(proj_logdet_cone)(scs_float *tvX, const scs_int n, ScsConeWork *c,
                               scs_int offset, bool *warmstart);
@@ -54,6 +47,13 @@ void SCS(proj_ell_one)(scs_float *tx, size_t n, ScsConeWork *c);
 scs_int SCS(proj_sum_largest_evals)(scs_float *tX, scs_int n, scs_int k,
                                     ScsConeWork *c);
 
+#endif
+
+/* Forward declare exponential cone projection routine.
+ * Implemented in exp_cone.c.
+ */
+scs_float SCS(proj_pd_exp_cone)(scs_float *v0, scs_int primal);
+
 void SCS(free_cone)(ScsCone *k) {
   if (k) {
     if (k->bu)

src/spectral_cones/logdeterminant/log_cone_IPM.c

@@ -33,11 +33,19 @@ scs_float d_one = 1.0;
 scs_float d_minus_one = -1.0;
 blas_int bi_three = 3;
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 void BLAS(gemv)(const char *trans, const blas_int *m, const blas_int *n,
                 const scs_float *alpha, const scs_float *a, const blas_int *lda,
                 const scs_float *x, const blas_int *incx, const scs_float *beta,
                 scs_float *y, const blas_int *incy);
 
+#ifdef __cplusplus
+}
+#endif
+
 /* Evaluates the oracle f(u) = (f0(u), f1(u), f2(u)) where u = [t, v, x, r]
  *  and
  *  f0 = 0.5 * (t - t0)^2 + 0.5 * (v - v0)^2 + 0.5 * ||x - x0||^2  - r

src/spectral_cones/logdeterminant/logdet_cone.c

@@ -18,6 +18,10 @@
  * Last modified: 25 August 2024.
  */
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 void BLAS(syev)(const char *jobz, const char *uplo, blas_int *n, scs_float *a,
                 blas_int *lda, scs_float *w, scs_float *work, blas_int *lwork,
                 blas_int *info);
@@ -28,6 +32,11 @@ blas_int BLAS(syrk)(const char *uplo, const char *trans, const blas_int *n,
 void BLAS(scal)(const blas_int *n, const scs_float *sa, scs_float *sx,
                 const blas_int *incx);
 
+#ifdef __cplusplus
+}
+#endif
+
+
 // forward declare from log_cone_wrapper.c
 scs_int log_cone_proj_wrapper(scs_float t0, scs_float v0, const scs_float *x0,
                               scs_float *proj, scs_int n, scs_float *workspace,

src/spectral_cones/nuclear/nuclear_cone.c

@@ -16,6 +16,11 @@
  * 
  * Last modified: 25 August 2024.
  */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 void BLAS(gemm)(const char *transa, const char *transb, blas_int *m,
                 blas_int *n, blas_int *k, scs_float *alpha, scs_float *a,
                 blas_int *lda, scs_float *b, blas_int *ldb, scs_float *beta,
@@ -30,6 +35,10 @@ void BLAS(gesvd)(const char *jobu, const char *jobvt, const blas_int *m,
                  const blas_int *ldvt, scs_float *work, const blas_int *lwork,
                  blas_int *info);
 
+#ifdef __cplusplus
+}
+#endif
+
 // forward declaration from ell1_cone.c
 scs_int ell1_cone_proj_sorted(scs_float t0, const scs_float *x0, scs_float *proj,
                               scs_int n);

src/spectral_cones/util_spectral_cones.c

@@ -32,9 +32,9 @@ void non_neg_proj(const scs_float *src, scs_float *dst, scs_int n)
     }
 }
 
-void print_vector(const scs_float *x, size_t n)
+void print_vector(const scs_float *x, scs_int n)
 {
-    for (size_t i = 0; i < n; ++i)
+    for (scs_int i = 0; i < n; ++i)
     {
         printf("%f ", x[i]);
     }
@@ -45,7 +45,7 @@ scs_float min_vec(const scs_float *vec, scs_int n)
 {
     scs_float minVal = vec[0];
 
-    for (size_t i = 1; i < n; ++i)
+    for (scs_int i = 1; i < n; ++i)
     {
         if (vec[i] < minVal)
         {