Test MSVC warnings

.github/problem-matchers/msvc.json

@@ -0,0 +1,19 @@
+{
+  "__comment": "Based on vscode's vs/workbench/contrib/tasks/common/problemMatcher.ts msCompile rule",
+  "problemMatcher": [
+    {
+      "owner": "msvc-problem-matcher",
+      "pattern": [
+        {
+          "regexp": "^\\s*(?:\\d+\\>)?(\\S.*)\\((\\d+),?(\\d+)?(?:,\\d+,\\d+)?\\)\\s*:\\s+((?:fatal +)?error|warning|info)\\s+((?!C4244|C4267)\\w+\\d+)\\s*:\\s*(.*)$",
+          "file": 1,
+          "line": 2,
+          "column": 3,
+          "severity": 4,
+          "code": 5,
+          "message": 6
+        }
+      ]
+    }
+  ]
+}

.github/workflows/test-windows.yml

@@ -164,6 +164,10 @@ jobs:
       run: rmdir /S /Q winbuild\build\src
       shell: cmd
 
+    - name: Register MSVC problem matcher
+      if: "matrix.python-version == '3.12'"
+      run: echo "::add-matcher::.github/problem-matchers/msvc.json"
+
     - name: Build Pillow
       run: |
         $FLAGS="-C raqm=vendor -C fribidi=vendor"

src/_webp.c

@@ -873,7 +873,7 @@ WebPDecode_wrapper(PyObject *self, PyObject *args) {
 // Return the decoder's version number, packed in hexadecimal using 8bits for
 // each of major/minor/revision. E.g: v2.5.7 is 0x020507.
 PyObject *
-WebPDecoderVersion_wrapper() {
+WebPDecoderVersion_wrapper(PyObject *self, PyObject *Py_UNUSED(args)) {
     return Py_BuildValue("i", WebPGetDecoderVersion());
 }
 
@@ -901,7 +901,7 @@ WebPDecoderBuggyAlpha(void) {
 }
 
 PyObject *
-WebPDecoderBuggyAlpha_wrapper() {
+WebPDecoderBuggyAlpha_wrapper(PyObject *self, PyObject *Py_UNUSED(args)) {
     return Py_BuildValue("i", WebPDecoderBuggyAlpha());
 }
 

src/display.c

@@ -427,7 +427,6 @@ PyImaging_GrabScreenWin32(PyObject *self, PyObject *args) {
 
 PyObject *
 PyImaging_GrabClipboardWin32(PyObject *self, PyObject *args) {
-    int clip;
     HANDLE handle = NULL;
     int size;
     void *data;

src/libImaging/Draw.c

@@ -34,6 +34,7 @@
 
 #include "Imaging.h"
 
+#define _USE_MATH_DEFINES
 #include <math.h>
 #include <stdint.h>
 

src/libImaging/Imaging.h

@@ -16,10 +16,6 @@
 extern "C" {
 #endif
 
-#ifndef M_PI
-#define M_PI 3.1415926535897932384626433832795
-#endif
-
 /* -------------------------------------------------------------------- */
 
 /*

src/libImaging/QuantOctree.c

@@ -367,7 +367,7 @@ map_image_pixels(
     uint32_t nPixels,
     const ColorCube lookupCube,
     uint32_t *pixelArray) {
-    long i;
+    unsigned long i;
     for (i = 0; i < nPixels; i++) {
         pixelArray[i] = lookup_color(lookupCube, &pixelData[i]);
     }
@@ -393,7 +393,7 @@ quantize_octree(
     ColorBucket paletteBucketsFine = NULL;
     ColorBucket paletteBuckets = NULL;
     uint32_t *qp = NULL;
-    long i;
+    unsigned long i;
     unsigned long nCoarseColors, nFineColors, nAlreadySubtracted;
     const unsigned int *cubeBits;
 

src/libImaging/QuantPngQuant.c

@@ -125,7 +125,7 @@ const char *
 ImagingImageQuantVersion(void) {
     static char version[20];
     int number = liq_version();
-    sprintf(version, "%d.%d.%d", number / 10000, (number / 100) % 100, number % 100);
+    snprintf(version, 20, "%d.%d.%d", number / 10000, (number / 100) % 100, number % 100);
     return version;
 }
 

src/libImaging/Resample.c

@@ -1,5 +1,6 @@
 #include "Imaging.h"
 
+#define _USE_MATH_DEFINES
 #include <math.h>
 
 #define ROUND_UP(f) ((int)((f) >= 0.0 ? (f) + 0.5F : (f)-0.5F))

src/libImaging/TiffDecode.c

@@ -973,7 +973,10 @@ ImagingLibTiffEncode(Imaging im, ImagingCodecState state, UINT8 *buffer, int byt
     }
 
     if (state->state == 1 && !clientstate->fp) {
-        int read = (int)_tiffReadProc(clientstate, (tdata_t)buffer, (tsize_t)bytes);
+        int read = (int)_tiffReadProc(
+            (thandle_t)clientstate,
+            (tdata_t)buffer,
+            (tsize_t)bytes);
         TRACE(
             ("Buffer: %p: %c%c%c%c\n",
              buffer,