Avoid 'clang' optimization, keep it -O0

pkg/storage/erasure/decode.c

@@ -46,6 +46,10 @@ int32_t minio_get_source_target (int errs, int k, int m,
         uint8_t *tmp_source[k];
         uint8_t *tmp_target[m];
 
+        if (k < 0 || m < 0) {
+                return -1;
+        }
+
         memset (tmp_source, 0, k);
         memset (tmp_target, 0, m);
 

pkg/storage/erasure/decode.go

@@ -19,6 +19,7 @@
 package erasure
 
 // #cgo CPPFLAGS: -Iisal/include
+// #cgo CFLAGS: -O0
 // #include <stdlib.h>
 // #include <erasure-code.h>
 //
@@ -81,9 +82,13 @@ func (e *Encoder) Decode(chunks [][]byte, length int) ([]byte, error) {
 
 	data := (**C.uint8_t)(unsafe.Pointer(&pointers[0]))
 
-	C.minio_get_source_target(C.int(err_count-1), e.k, e.m, error_index_ptr,
+	ret := C.minio_get_source_target(C.int(err_count-1), e.k, e.m, error_index_ptr,
 		decode_index, data, &source, &target)
 
+	if int(ret) == -1 {
+		return nil, errors.New("Decoding source target failed")
+	}
+
 	C.ec_encode_data(C.int(chunk_size), e.k, C.int(err_count-1), decode_tbls,
 		source, target)
 

pkg/storage/erasure/encode.go

@@ -20,6 +20,7 @@ package erasure
 
 // #cgo CPPFLAGS: -Iisal/include
 // #cgo LDFLAGS: isal/isa-l.a
+// #cgo CFLAGS: -O0
 // #include <stdlib.h>
 // #include <erasure-code.h>
 //