cython producing error-prone code in __pyx_import_star_set with C macros

[Vasilis Stamelos]

hello, i have been trying to learn vulkan with cython and i have hit a wall cause the C compiler throws this error `error C2106: '=': left operand must be l-value`

code: <https://github.com/Emc2356/CyVulkan>

this is the actual code that throws the error in the C++ source:

```cpp

else if (__Pyx_StrEq(name, "GLFW_CLIENT_API")) {
     GLFW_CLIENT_API = _Pyx_PyInt_As_int(o); if (unlikely((GLFW_CLIENT_API == (int)-1) && PyErr_Occurred())) __PYX_ERR(1, 293, __pyx_L2_error)
}

```

which will expand to

`139265 = _Pyx_PyInt_As_int(o); `

what can i do to fix this error?

[da-woods]

It'd be useful if you could show the code that generated it rather than just linking to a Github repository (which has quite a few files to look through, and no doubt needs headers to be installed even if we wanted to try compiling it ourselves). The relevant code should be in comments right next to the C++ code that's failing.

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[Vasilis Stamelos]

after i searched the source i could find only one instance of GLFW_CLIENT_API being used

```py
cdef GLFWwindow* create_window(int width, int height, char* windowName):
     glfwInit()
     glfwWindowHint(GLFW_CLIENT_API, GLFW_NO_API)
     glfwWindowHint(GLFW_RESIZABLE, GLFW_FALSE)
     return glfwCreateWindow(width, height, windowName, NULL, NULL)

```

the only other place that it was mention was in CyGlfw.pxd inside a `cdef extern from` block with the type of int

i hope this helped but i dont know what i am supposed to look for

[da-woods]

Right - I can reproduce it with a pxd file:

cdef extern from *:
    int SOME_MACRO

and a pyx file:

from cimportstarpxd cimport *

from somewhere_else import *

def f():
    print(SOME_MACRO)

------------------------

Essentially, it believes SOME_MACRO is a writeable integer. It doesn't know what gets imported from "somewhere_else" but will reassign SOME_MACRO if "somewhere_else" defines that value.

Your options are:

1) avoid "import *" and/or "cimport *"

2) Define "SOME_MACRO" differently - e.g. as a member of an extern enum (it doesn't believe enums can be reassigned):

         cdef enum:
            SOME_MACRO

David

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