[libcxx-commits] [libcxx] [libcxx] coerce formatter literal to int32_t (PR #87738)

[via libcxx-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-libcxx

Author: Brian Cain (androm3da)

<details>
<summary>Changes</summary>

__precision_ is declared as an int32_t which on some hexagon platforms is defined as a long.

This change fixes errors like the ones below:

    In file included from /local/mnt/workspace/hex/llvm-project/libcxx/test/libcxx/diagnostics/format.nodiscard_extensions.compile.pass.cpp:19:
    In file included from /local/mnt/workspace/hex/obj_runtimes_hex88_qurt_v75_ON_ON_shared/include/c++/v1/format:202:
    In file included from /local/mnt/workspace/hex/obj_runtimes_hex88_qurt_v75_ON_ON_shared/include/c++/v1/__format/format_functions.h:29:
    /local/mnt/workspace/hex/obj_runtimes_hex88_qurt_v75_ON_ON_shared/include/c++/v1/__format/formatter_floating_point.h:700:17: error: no matching function for call to 'max'
      700 |       int __p = std::max(1, (__specs.__has_precision() ? __specs.__precision_ : 6));
          |                 ^~~~~~~~
    /local/mnt/workspace/hex/obj_runtimes_hex88_qurt_v75_ON_ON_shared/include/c++/v1/__format/formatter_floating_point.h:771:25: note: in instantiation of function template specialization 'std::__formatter::__format_floating_point<float, char, std::format_context>' requested here
      771 |     return __formatter::__format_floating_point(__value, __ctx, __parser_.__get_parsed_std_specifications(__ctx));
          |                         ^
    /local/mnt/workspace/hex/obj_runtimes_hex88_qurt_v75_ON_ON_shared/include/c++/v1/__format/format_functions.h:284:42: note: in instantiation of function template specialization 'std::__formatter_floating_point<char>::format<float, std::format_context>' requested here
      284 |             __ctx.advance_to(__formatter.format(__arg, __ctx));
          |                                          ^
    /local/mnt/workspace/hex/obj_runtimes_hex88_qurt_v75_ON_ON_shared/include/c++/v1/__format/format_functions.h:429:15: note: in instantiation of function template specialization 'std::__vformat_to<std::back_insert_iterator<std::string>, char, std::back_insert_iterator<std::__format::__output_buffer<char>>>' requested here
      429 |   return std::__vformat_to(std::move(__out_it), __fmt, __args);
          |               ^
    /local/mnt/workspace/hex/obj_runtimes_hex88_qurt_v75_ON_ON_shared/include/c++/v1/__format/format_functions.h:462:8: note: in instantiation of function template specialization 'std::vformat_to<std::back_insert_iterator<std::string>>' requested here
      462 |   std::vformat_to(std::back_inserter(__res), __fmt, __args);
          |        ^
    /local/mnt/workspace/hex/llvm-project/libcxx/test/libcxx/diagnostics/format.nodiscard_extensions.compile.pass.cpp:29:8: note: in instantiation of function template specialization 'std::vformat<void>' requested here
       29 |   std::vformat("", std::make_format_args());
          |        ^
    /local/mnt/workspace/hex/obj_runtimes_hex88_qurt_v75_ON_ON_shared/include/c++/v1/__algorithm/max.h:35:1: note: candidate template ignored: deduced conflicting types for parameter '_Tp' ('int' vs. 'int32_t' (aka 'long'))
       35 | max(_LIBCPP_LIFETIMEBOUND const _Tp& __a, _LIBCPP_LIFETIMEBOUND const _Tp& __b) {
          | ^
    /local/mnt/workspace/hex/obj_runtimes_hex88_qurt_v75_ON_ON_shared/include/c++/v1/__algorithm/max.h:43:1: note: candidate template ignored: could not match 'initializer_list<_Tp>' against 'int'
       43 | max(initializer_list<_Tp> __t, _Compare __comp) {
          | ^
    /local/mnt/workspace/hex/obj_runtimes_hex88_qurt_v75_ON_ON_shared/include/c++/v1/__algorithm/max.h:48:86: note: candidate function template not viable: requires single argument '__t', but 2 arguments were provided
       48 | _LIBCPP_NODISCARD_EXT inline _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 _Tp max(initializer_list<_Tp> __t) {
          |                                                                                      ^   ~~~~~~~~~~~~~~~~~~~~~~~~~
    /local/mnt/workspace/hex/obj_runtimes_hex88_qurt_v75_ON_ON_shared/include/c++/v1/__algorithm/max.h:29:1: note: candidate function template not viable: requires 3 arguments, but 2 were provided
       29 | max(_LIBCPP_LIFETIMEBOUND const _Tp& __a, _LIBCPP_LIFETIMEBOUND const _Tp& __b, _Compare __comp) {
          | ^                         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

---
Full diff: https://github.com/llvm/llvm-project/pull/87738.diff


1 Files Affected:

- (modified) libcxx/include/__format/formatter_floating_point.h (+1-1) 


``````````diff
diff --git a/libcxx/include/__format/formatter_floating_point.h b/libcxx/include/__format/formatter_floating_point.h
index 1d94cc349c0dd6..0aaea646a4066c 100644
--- a/libcxx/include/__format/formatter_floating_point.h
+++ b/libcxx/include/__format/formatter_floating_point.h
@@ -690,7 +690,7 @@ __format_floating_point(_Tp __value, _FormatContext& __ctx, __format_spec::__par
       // Let P equal the precision if nonzero, 6 if the precision is not
       // specified, or 1 if the precision is 0. Then, if a conversion with
       // style E would have an exponent of X:
-      int __p = std::max(1, (__specs.__has_precision() ? __specs.__precision_ : 6));
+      int __p = std::max(int32_t(1), (__specs.__has_precision() ? __specs.__precision_ : 6));
       if (__result.__exponent == __result.__last)
         // if P > X >= -4, the conversion is with style f or F and precision P - 1 - X.
         // By including the radix point it calculates P - (1 + X)

``````````

</details>


https://github.com/llvm/llvm-project/pull/87738