zlib-ng: avoid suppressing WD4242 and WD4244 (#105433)

WD4242 and WD4244 are compiler warnings that should not be suppressed because the warn about possible loss of data.

WD4242 shows up in zlib-ng/arch/*/slide_hash*.c files and comes from the arguments passed to the slide_hash_chain method.
WD4244 happens in Windows when building in Debug configuration, in various zlib-ng/deflate*.c files, and comes from the arguments passed to the check_match method.

Fixed by:

- Adding asserts to verify the values are below the maximum allowed for their type.
- Casting them the proper type before passing them as arguments to their methods.
- Removing the WD suppressions, which unfortunately also propagated to other unrelated cmake files.
- Fixed a similar loss of data error in an unrelated mono file where the warning suppression was propagated due to this.

src/mono/mono/metadata/class-internals.h

@@ -1467,7 +1467,7 @@ mono_method_has_unmanaged_callers_only_attribute (MonoMethod *method);
 
 typedef struct _MonoVarianceSearchTableEntry {
     MonoClass *klass;
-    guint16 offset;
+    int offset;
 } MonoVarianceSearchTableEntry;
 
 MonoVarianceSearchTableEntry *

src/native/external/zlib-ng-version.txt

@@ -8,3 +8,5 @@ We have removed the following folders from our local copy as these files are not
 - zlib-ng/docs/
 - zlib-ng/test/
 - zlib-ng/arch/s390/self-hosted-builder/
+
+Apply https://github.com/dotnet/runtime/pull/105433.patch

src/native/external/zlib-ng.cmake

@@ -1,3 +1,5 @@
+ # IMPORTANT: do not use add_compile_options(), add_definitions() or similar functions here since it will leak to the including projects 
+
 include(FetchContent)
 
 FetchContent_Declare(
@@ -12,12 +14,6 @@ set(Z_PREFIX ON)
 # TODO: Turn back on when Linux kernels with proper RISC-V extension detection (>= 6.5) are more commonplace
 set(WITH_RVV OFF)
 
-add_compile_options($<$<COMPILE_LANG_AND_ID:C,Clang,AppleClang>:-Wno-unused-command-line-argument>) # clang : error : argument unused during compilation: '-fno-semantic-interposition'
-add_compile_options($<$<COMPILE_LANG_AND_ID:C,Clang,AppleClang>:-Wno-logical-op-parentheses>) # place parentheses around the '&&' expression to silence this warning
-add_compile_options($<$<COMPILE_LANG_AND_ID:C,MSVC>:/wd4127>) # warning C4127: conditional expression is constant
-add_compile_options($<$<COMPILE_LANG_AND_ID:C,MSVC>:/wd4242>) # 'function': conversion from 'unsigned int' to 'Pos', possible loss of data, in various deflate_*.c files
-add_compile_options($<$<COMPILE_LANG_AND_ID:C,MSVC>:/wd4244>) # 'function': conversion from 'unsigned int' to 'Pos', possible loss of data, in various deflate_*.c files
-
 # 'aligned_alloc' is not available in browser/wasi, yet it is set by zlib-ng/CMakeLists.txt.
 if (CLR_CMAKE_TARGET_BROWSER OR CLR_CMAKE_TARGET_WASI)
   set(HAVE_ALIGNED_ALLOC FALSE CACHE BOOL "have aligned_alloc" FORCE)
@@ -31,6 +27,7 @@ set(SKIP_INSTALL_ALL OFF)
 set_property(DIRECTORY ${CMAKE_CURRENT_LIST_DIR}/zlib-ng PROPERTY MSVC_WARNING_LEVEL 3) # Set the MSVC warning level for all zlib-ng targets to 3.
 target_compile_options(zlib PRIVATE $<$<COMPILE_LANG_AND_ID:C,Clang,AppleClang>:-Wno-unused-command-line-argument>) # Make sure MacOS respects ignoring unused CLI arguments
 target_compile_options(zlib PRIVATE $<$<COMPILE_LANG_AND_ID:C,Clang,AppleClang>:-Wno-logical-op-parentheses>) # place parentheses around the '&&' expression to silence this warning
+target_compile_options(zlib PRIVATE $<$<COMPILE_LANG_AND_ID:C,MSVC>:/wd4127>) # warning C4127: conditional expression is constant
 target_compile_options(zlib PRIVATE $<$<COMPILE_LANG_AND_ID:C,MSVC>:/guard:cf>) # Enable CFG always for zlib-ng so we don't need to build two flavors.
 
 set_target_properties(zlib PROPERTIES DEBUG_POSTFIX "") # Workaround: zlib's debug lib name is zlibd.lib

src/native/external/zlib-ng/arch/arm/slide_hash_armv6.c

@@ -39,7 +39,8 @@ static inline void slide_hash_chain(Pos *table, uint32_t entries, uint16_t wsize
 }
 
 Z_INTERNAL void slide_hash_armv6(deflate_state *s) {
-    unsigned int wsize = s->w_size;
+    Assert(s->w_size <= UINT16_MAX, "w_size should fit in uint16_t");
+    uint16_t wsize = (uint16_t)s->w_size;
 
     slide_hash_chain(s->head, HASH_SIZE, wsize);
     slide_hash_chain(s->prev, wsize, wsize);

src/native/external/zlib-ng/arch/arm/slide_hash_neon.c

@@ -38,7 +38,8 @@ static inline void slide_hash_chain(Pos *table, uint32_t entries, uint16_t wsize
 }
 
 Z_INTERNAL void slide_hash_neon(deflate_state *s) {
-    unsigned int wsize = s->w_size;
+    Assert(s->w_size <= UINT16_MAX, "w_size should fit in uint16_t");
+    uint16_t wsize = (uint16_t)s->w_size;
 
     slide_hash_chain(s->head, HASH_SIZE, wsize);
     slide_hash_chain(s->prev, wsize, wsize);

src/native/external/zlib-ng/arch/power/slide_ppc_tpl.h

@@ -24,7 +24,8 @@ static inline void slide_hash_chain(Pos *table, uint32_t entries, uint16_t wsize
 }
 
 void Z_INTERNAL SLIDE_PPC(deflate_state *s) {
-    uint16_t wsize = s->w_size;
+    Assert(s->w_size <= UINT16_MAX, "w_size should fit in uint16_t");
+    uint16_t wsize = (uint16_t)s->w_size;
 
     slide_hash_chain(s->head, HASH_SIZE, wsize);
     slide_hash_chain(s->prev, wsize, wsize);

src/native/external/zlib-ng/arch/riscv/slide_hash_rvv.c

@@ -25,6 +25,7 @@ static inline void slide_hash_chain(Pos *table, uint32_t entries, uint16_t wsize
 }
 
 Z_INTERNAL void slide_hash_rvv(deflate_state *s) {
+    Assert(s->w_size <= UINT16_MAX, "w_size should fit in uint16_t");
     uint16_t wsize = (uint16_t)s->w_size;
 
     slide_hash_chain(s->head, HASH_SIZE, wsize);

src/native/external/zlib-ng/arch/x86/slide_hash_avx2.c

@@ -31,6 +31,7 @@ static inline void slide_hash_chain(Pos *table, uint32_t entries, const __m256i
 }
 
 Z_INTERNAL void slide_hash_avx2(deflate_state *s) {
+    Assert(s->w_size <= UINT16_MAX, "w_size should fit in uint16_t");
     uint16_t wsize = (uint16_t)s->w_size;
     const __m256i ymm_wsize = _mm256_set1_epi16((short)wsize);
 

src/native/external/zlib-ng/arch/x86/slide_hash_sse2.c

@@ -52,6 +52,7 @@ static inline void slide_hash_chain(Pos *table0, Pos *table1, uint32_t entries0,
 }
 
 Z_INTERNAL void slide_hash_sse2(deflate_state *s) {
+    Assert(s->w_size <= UINT16_MAX, "w_size should fit in uint16_t");
     uint16_t wsize = (uint16_t)s->w_size;
     const __m128i xmm_wsize = _mm_set1_epi16((short)wsize);
 

src/native/external/zlib-ng/deflate_fast.c

@@ -58,7 +58,9 @@ Z_INTERNAL block_state deflate_fast(deflate_state *s, int flush) {
         }
 
         if (match_len >= WANT_MIN_MATCH) {
-            check_match(s, s->strstart, s->match_start, match_len);
+            Assert(s->strstart <= UINT16_MAX, "strstart should fit in uint16_t");
+            Assert(s->match_start <= UINT16_MAX, "match_start should fit in uint16_t");
+            check_match(s, (Pos)s->strstart, (Pos)s->match_start, match_len);
 
             bflush = zng_tr_tally_dist(s, s->strstart - s->match_start, match_len - STD_MIN_MATCH);
 

src/native/external/zlib-ng/deflate_quick.c

@@ -102,7 +102,8 @@ Z_INTERNAL block_state deflate_quick(deflate_state *s, int flush) {
                         if (UNLIKELY(match_len > STD_MAX_MATCH))
                             match_len = STD_MAX_MATCH;
 
-                        check_match(s, s->strstart, hash_head, match_len);
+                        Assert(s->strstart <= UINT16_MAX, "strstart should fit in uint16_t");
+                        check_match(s, (Pos)s->strstart, hash_head, match_len);
 
                         zng_tr_emit_dist(s, static_ltree, static_dtree, match_len - STD_MIN_MATCH, (uint32_t)dist);
                         s->lookahead -= match_len;

src/native/external/zlib-ng/deflate_rle.c

@@ -58,7 +58,9 @@ Z_INTERNAL block_state deflate_rle(deflate_state *s, int flush) {
 
         /* Emit match if have run of STD_MIN_MATCH or longer, else emit literal */
         if (match_len >= STD_MIN_MATCH) {
-            check_match(s, s->strstart, s->strstart - 1, match_len);
+            Assert(s->strstart <= UINT16_MAX, "strstart should fit in uint16_t");
+            Assert(s->match_start <= UINT16_MAX, "match_start should fit in uint16_t");
+            check_match(s, (Pos)s->strstart, (Pos)s->strstart - 1, match_len);
 
             bflush = zng_tr_tally_dist(s, 1, match_len - STD_MIN_MATCH);
 

src/native/external/zlib-ng/deflate_slow.c

@@ -78,7 +78,8 @@ Z_INTERNAL block_state deflate_slow(deflate_state *s, int flush) {
             unsigned int max_insert = s->strstart + s->lookahead - STD_MIN_MATCH;
             /* Do not insert strings in hash table beyond this. */
 
-            check_match(s, s->strstart-1, s->prev_match, s->prev_length);
+            Assert((s->strstart-1) <= UINT16_MAX, "strstart-1 should fit in uint16_t");
+            check_match(s, (Pos)(s->strstart-1), s->prev_match, s->prev_length);
 
             bflush = zng_tr_tally_dist(s, s->strstart -1 - s->prev_match, s->prev_length - STD_MIN_MATCH);