Revert "[libc] Enable -Wconversion for tests. (#127523)"

This reverts commit 1e6e845d49a336e9da7ca6c576ec45c0b419b5f6 because it
changed the 1st parameter of adjust() to be unsigned, but libc itself
calls adjust() with a negative argument in align_backward() in
op_generic.h.

3 files changed, 15 insertions, 19 deletions

diff --git a/libc/src/stdio/printf_core/parser.h b/libc/src/stdio/printf_core/parser.h
index 89556f1a9e5f..acbbaa25b1c9 100644
--- a/libc/src/stdio/printf_core/parser.h
+++ b/libc/src/stdio/printf_core/parser.h
@@ -57,8 +57,7 @@ template <typename T> using int_type_of_v = typename int_type_of<T>::type;
     if (!temp.has_value()) {                                                   \
       section.has_conv = false;                                                \
     } else {                                                                   \
-      dst = static_cast<decltype(dst)>(                                        \
-          cpp::bit_cast<int_type_of_v<arg_type>>(temp.value()));               \
+      dst = cpp::bit_cast<int_type_of_v<arg_type>>(temp.value());              \
     }                                                                          \
   }
 #else
@@ -131,7 +130,7 @@ public:
       } else if (internal::isdigit(str[cur_pos])) {
         auto result = internal::strtointeger<int>(str + cur_pos, 10);
         section.min_width = result.value;
-        cur_pos = cur_pos + static_cast<size_t>(result.parsed_len);
+        cur_pos = cur_pos + result.parsed_len;
       }
       if (section.min_width < 0) {
         section.min_width =
@@ -154,7 +153,7 @@ public:
         } else if (internal::isdigit(str[cur_pos])) {
           auto result = internal::strtointeger<int>(str + cur_pos, 10);
           section.precision = result.value;
-          cur_pos = cur_pos + static_cast<size_t>(result.parsed_len);
+          cur_pos = cur_pos + result.parsed_len;
         }
       }
 
@@ -266,8 +265,7 @@ public:
       case ('m'):
         // %m is an odd conversion in that it doesn't consume an argument, it
         // just takes the current value of errno as its argument.
-        section.conv_val_raw =
-            static_cast<fputil::FPBits<double>::StorageType>(libc_errno);
+        section.conv_val_raw = static_cast<int>(libc_errno);
         break;
 #endif // LIBC_COPT_PRINTF_DISABLE_STRERROR
 #ifndef LIBC_COPT_PRINTF_DISABLE_WRITE_INT
@@ -358,7 +356,7 @@ private:
       }
       if (internal::isdigit(str[*local_pos])) {
         const auto result = internal::strtointeger<int>(str + *local_pos, 10);
-        *local_pos += static_cast<size_t>(result.parsed_len);
+        *local_pos += result.parsed_len;
         return {lm, static_cast<size_t>(cpp::max(0, result.value))};
       }
       return {lm, 0};
@@ -407,10 +405,10 @@ private:
   LIBC_INLINE size_t parse_index(size_t *local_pos) {
     if (internal::isdigit(str[*local_pos])) {
       auto result = internal::strtointeger<int>(str + *local_pos, 10);
-      size_t index = static_cast<size_t>(result.value);
-      if (str[*local_pos + static_cast<size_t>(result.parsed_len)] != '$')
+      size_t index = result.value;
+      if (str[*local_pos + result.parsed_len] != '$')
         return 0;
-      *local_pos = static_cast<size_t>(1 + result.parsed_len) + *local_pos;
+      *local_pos = 1 + result.parsed_len + *local_pos;
       return index;
     }
     return 0;
diff --git a/libc/src/stdio/printf_core/writer.h b/libc/src/stdio/printf_core/writer.h
index 28c9a2827087..5526a478ea62 100644
--- a/libc/src/stdio/printf_core/writer.h
+++ b/libc/src/stdio/printf_core/writer.h
@@ -135,8 +135,7 @@ public:
     chars_written += static_cast<int>(length);
 
     if (LIBC_LIKELY(wb->buff_cur + length <= wb->buff_len)) {
-      inline_memset(wb->buff + wb->buff_cur,
-                    static_cast<unsigned char>(new_char), length);
+      inline_memset(wb->buff + wb->buff_cur, new_char, length);
       wb->buff_cur += length;
       return WRITE_OK;
     }
diff --git a/libc/src/stdio/scanf_core/parser.h b/libc/src/stdio/scanf_core/parser.h
index 1e2f26e0d3fd..6cc5b30eb0db 100644
--- a/libc/src/stdio/scanf_core/parser.h
+++ b/libc/src/stdio/scanf_core/parser.h
@@ -78,7 +78,7 @@ public:
       if (internal::isdigit(str[cur_pos])) {
         auto result = internal::strtointeger<int>(str + cur_pos, 10);
         section.max_width = result.value;
-        cur_pos = cur_pos + static_cast<size_t>(result.parsed_len);
+        cur_pos = cur_pos + result.parsed_len;
       }
 
       // TODO(michaelrj): add posix allocate flag support.
@@ -150,11 +150,10 @@ public:
             char b = str[cur_pos + 1];
             char start = (a < b ? a : b);
             char end = (a < b ? b : a);
-            scan_set.set_range(static_cast<size_t>(start),
-                               static_cast<size_t>(end));
+            scan_set.set_range(start, end);
             cur_pos += 2;
           } else {
-            scan_set.set(static_cast<size_t>(str[cur_pos]));
+            scan_set.set(str[cur_pos]);
             ++cur_pos;
           }
         }
@@ -238,10 +237,10 @@ private:
   LIBC_INLINE size_t parse_index(size_t *local_pos) {
     if (internal::isdigit(str[*local_pos])) {
       auto result = internal::strtointeger<int>(str + *local_pos, 10);
-      size_t index = static_cast<size_t>(result.value);
-      if (str[*local_pos + static_cast<size_t>(result.parsed_len)] != '$')
+      size_t index = result.value;
+      if (str[*local_pos + result.parsed_len] != '$')
         return 0;
-      *local_pos = static_cast<size_t>(1 + result.parsed_len) + *local_pos;
+      *local_pos = 1 + result.parsed_len + *local_pos;
       return index;
     }
     return 0;