Remove 4146 from libunwind (dotnet#66427)

* Remove 4146 from libunwind Use existing libunwind align macro and use casting when the operation's target should reflect a signed value.
radekdoulik · Mar 30, 2022 · be40f94 · be40f94
1 parent 89542e5
commit be40f94
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Showing 5 changed files with 8 additions and 9 deletions.
diff --git a/src/coreclr/pal/src/libunwind/CMakeLists.txt b/src/coreclr/pal/src/libunwind/CMakeLists.txt
@@ -157,7 +157,6 @@ if(CLR_CMAKE_HOST_WIN32)
 
     # Warnings in release builds
     add_compile_options(-wd4068) # ignore unknown pragma warnings (gcc pragmas)
-    add_compile_options(-wd4146) # minus operator applied to unsigned
     add_compile_options(-wd4244) # possible loss of data
     add_compile_options(-wd4334) # 32-bit shift implicitly converted to 64 bits
 

diff --git a/src/coreclr/pal/src/libunwind/include/dwarf_i.h b/src/coreclr/pal/src/libunwind/include/dwarf_i.h
@@ -136,7 +136,7 @@ static inline int
 dwarf_readu8 (unw_addr_space_t as, unw_accessors_t *a, unw_word_t *addr,
               uint8_t *valp, void *arg)
 {
-  unw_word_t val, aligned_addr = *addr & -sizeof (unw_word_t);
+  unw_word_t val, aligned_addr = UNW_ALIGN(*addr, sizeof (unw_word_t));
   unw_word_t off = *addr - aligned_addr;
   int ret;
 

diff --git a/src/coreclr/pal/src/libunwind/include/remote.h b/src/coreclr/pal/src/libunwind/include/remote.h
@@ -51,7 +51,7 @@ static inline int
 fetch8 (unw_addr_space_t as, unw_accessors_t *a,
         unw_word_t *addr, int8_t *valp, void *arg)
 {
-  unw_word_t val, aligned_addr = *addr & -WSIZE, off = *addr - aligned_addr;
+  unw_word_t val, aligned_addr = UNW_ALIGN(*addr, WSIZE), off = *addr - aligned_addr;
   int ret;
 
   *addr += 1;
@@ -71,7 +71,7 @@ static inline int
 fetch16 (unw_addr_space_t as, unw_accessors_t *a,
          unw_word_t *addr, int16_t *valp, void *arg)
 {
-  unw_word_t val, aligned_addr = *addr & -WSIZE, off = *addr - aligned_addr;
+  unw_word_t val, aligned_addr = UNW_ALIGN(*addr, WSIZE), off = *addr - aligned_addr;
   int ret;
 
   if ((off & 0x1) != 0)
@@ -94,7 +94,7 @@ static inline int
 fetch32 (unw_addr_space_t as, unw_accessors_t *a,
          unw_word_t *addr, int32_t *valp, void *arg)
 {
-  unw_word_t val, aligned_addr = *addr & -WSIZE, off = *addr - aligned_addr;
+  unw_word_t val, aligned_addr = UNW_ALIGN(*addr, WSIZE), off = *addr - aligned_addr;
   int ret;
 
   if ((off & 0x3) != 0)

diff --git a/src/coreclr/pal/src/libunwind/src/dwarf/Gexpr.c b/src/coreclr/pal/src/libunwind/src/dwarf/Gexpr.c
@@ -530,7 +530,7 @@ if (stackerror)                                 \
           Debug (15, "OP_abs\n");
           tmp1 = pop ();
           if (tmp1 & ((unw_word_t) 1 << (8 * dwarf_addr_size (as) - 1)))
-            tmp1 = -tmp1;
+            tmp1 = (unw_word_t)(-(unw_sword_t)tmp1);
           push (tmp1);
           break;
 
@@ -578,7 +578,7 @@ if (stackerror)                                 \
 
         case DW_OP_neg:
           Debug (15, "OP_neg\n");
-          push (-pop ());
+          push (-(unw_sword_t)pop ());
           break;
 
         case DW_OP_not:

diff --git a/src/coreclr/pal/src/libunwind/src/dwarf/Gparser.c b/src/coreclr/pal/src/libunwind/src/dwarf/Gparser.c
@@ -390,9 +390,9 @@ run_cfi_program (struct dwarf_cursor *c, dwarf_state_record_t *sr,
           if (((ret = read_regnum (as, a, addr, &regnum, arg)) < 0)
               || ((ret = dwarf_read_uleb128 (as, a, addr, &val, arg)) < 0))
             break;
-          set_reg (sr, regnum, DWARF_WHERE_CFAREL, -(val * dci->data_align));
+          set_reg (sr, regnum, DWARF_WHERE_CFAREL, (unw_word_t)(-(unw_sword_t)val));
           Debug (15, "CFA_GNU_negative_offset_extended cfa+0x%lx\n",
-                 (long) -(val * dci->data_align));
+                 (long)(unw_word_t)(-(unw_sword_t)val));
           break;
 
         case DW_CFA_GNU_window_save: