Compatibility with icu4c@75 from Homebrew #1398
Description
Homebrew has updated ICU4C and from version 75 it needs C++14 in the build.
Homebrew solves it using this environment variable during build:
Running a build for PHP 8.0 or PHP 8.1 with intl extension will give you this if you've updated icu4c via Homebrew
In file included from /Users/xxxxx/.phpbrew/build/php-8.1.32/ext/intl/intl_convertcpp.cpp:17:
In file included from /Users/xxxxx/.phpbrew/build/php-8.1.32/ext/intl/intl_convertcpp.h:22:
In file included from /opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/unistr.h:31:
In file included from /opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/utypes.h:39:
/opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/uversion.h:182:11: warning: nested namespace definition is a C++17 extension; define each namespace separately [-Wc++17-extensions]
182 | namespace U_HEADER_ONLY_NAMESPACE {}
| ^
/opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/uversion.h:180:48: note: expanded from macro 'U_HEADER_ONLY_NAMESPACE'
180 | #define U_HEADER_ONLY_NAMESPACE U_ICU_NAMESPACE::U_HEADER_NESTED_NAMESPACE
| ^
In file included from /Users/xxxxx/.phpbrew/build/php-8.1.32/ext/intl/intl_convertcpp.cpp:17:
In file included from /Users/xxxxx/.phpbrew/build/php-8.1.32/ext/intl/intl_convertcpp.h:22:
In file included from /opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/unistr.h:37:
/opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/char16ptr.h:271:38: error: no template named 'enable_if_t' in namespace 'std'
271 | template<typename T, typename = std::enable_if_t<std::is_same_v<T, UChar>>>
| ~~~~~^
/opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/char16ptr.h:271:55: error: no template named 'is_same_v' in namespace 'std'; did you mean 'is_same'?
271 | template<typename T, typename = std::enable_if_t<std::is_same_v<T, UChar>>>
| ~~~~~^~~~~~~~~
| is_same
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/c++/v1/__type_traits/is_same.h:22:29: note: 'is_same' declared here
22 | struct _LIBCPP_TEMPLATE_VIS is_same : _BoolConstant<__is_same(_Tp, _Up)> {};
| ^
In file included from /Users/xxxxx/.phpbrew/build/php-8.1.32/ext/intl/intl_convertcpp.cpp:17:
In file included from /Users/xxxxx/.phpbrew/build/php-8.1.32/ext/intl/intl_convertcpp.h:22:
In file included from /opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/unistr.h:37:
/opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/char16ptr.h:273:8: warning: constexpr if is a C++17 extension [-Wc++17-extensions]
273 | if constexpr (std::is_same_v<UChar, char16_t>) {
| ^
/opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/char16ptr.h:273:24: error: no template named 'is_same_v' in namespace 'std'; did you mean 'is_same'?
273 | if constexpr (std::is_same_v<UChar, char16_t>) {
| ~~~~~^~~~~~~~~
| is_same
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/c++/v1/__type_traits/is_same.h:22:29: note: 'is_same' declared here
22 | struct _LIBCPP_TEMPLATE_VIS is_same : _BoolConstant<__is_same(_Tp, _Up)> {};
| ^
In file included from /Users/xxxxx/.phpbrew/build/php-8.1.32/ext/intl/intl_convertcpp.cpp:17:
In file included from /Users/xxxxx/.phpbrew/build/php-8.1.32/ext/intl/intl_convertcpp.h:22:
In file included from /opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/unistr.h:37:
/opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/char16ptr.h:273:50: error: expected unqualified-id
273 | if constexpr (std::is_same_v<UChar, char16_t>) {
| ^
/opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/char16ptr.h:385:16: warning: variable templates are a C++14 extension [-Wc++14-extensions]
385 | constexpr bool ConvertibleToU16StringView =
| ^
/opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/char16ptr.h:386:10: error: no template named 'is_convertible_v' in namespace 'std'; did you mean 'is_convertible'?
386 | std::is_convertible_v<T, std::u16string_view>
| ~~~~~^~~~~~~~~~~~~~~~
| is_convertible
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/c++/v1/__type_traits/is_convertible.h:22:29: note: 'is_convertible' declared here
22 | struct _LIBCPP_TEMPLATE_VIS is_convertible : public integral_constant<bool, __is_convertible(_T1, _T2)> {};
| ^
In file included from /Users/xxxxx/.phpbrew/build/php-8.1.32/ext/intl/intl_convertcpp.cpp:17:
In file included from /Users/xxxxx/.phpbrew/build/php-8.1.32/ext/intl/intl_convertcpp.h:22:
In file included from /opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/unistr.h:37:
/opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/char16ptr.h:393:5: error: expected '(' for function-style cast or type construction
386 | std::is_convertible_v<T, std::u16string_view>
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
387 | #if !U_CHAR16_IS_TYPEDEF && (!defined(_LIBCPP_VERSION) || _LIBCPP_VERSION < 180000)
388 | || std::is_convertible_v<T, std::basic_string_view<uint16_t>>
389 | #endif
390 | #if U_SIZEOF_WCHAR_T==2
391 | || std::is_convertible_v<T, std::wstring_view>
392 | #endif
393 | ;
| ^
/opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/char16ptr.h:429:36: error: no type named 'enable_if_t' in namespace 'std'
429 | typename = typename std::enable_if_t<!std::is_pointer_v<std::remove_reference_t<T>>>>
| ~~~~~~~~~~~~~~^~~~~~~~~~~
/opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/char16ptr.h:429:47: error: expected ',' or '>' in template-parameter-list
429 | typename = typename std::enable_if_t<!std::is_pointer_v<std::remove_reference_t<T>>>>
| ^
/opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/char16ptr.h:429:93: error: expected unqualified-id
429 | typename = typename std::enable_if_t<!std::is_pointer_v<std::remove_reference_t<T>>>>
| ^
/opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/char16ptr.h:439:36: error: no type named 'enable_if_t' in namespace 'std'
439 | typename = typename std::enable_if_t<std::is_pointer_v<std::remove_reference_t<T>>>,
| ~~~~~~~~~~~~~~^~~~~~~~~~~
/opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/char16ptr.h:439:47: error: expected ',' or '>' in template-parameter-list
439 | typename = typename std::enable_if_t<std::is_pointer_v<std::remove_reference_t<T>>>,
| ^
/opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/char16ptr.h:439:92: error: expected unqualified-id
439 | typename = typename std::enable_if_t<std::is_pointer_v<std::remove_reference_t<T>>>,
| ^
In file included from /Users/xxxxx/.phpbrew/build/php-8.1.32/ext/intl/intl_convertcpp.cpp:17:
In file included from /Users/xxxxx/.phpbrew/build/php-8.1.32/ext/intl/intl_convertcpp.h:22:
In file included from /opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/unistr.h:40:
/opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/stringpiece.h:134:29: error: no template named 'enable_if_t' in namespace 'std'
134 | typename = std::enable_if_t<
| ~~~~~^
/opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/stringpiece.h:135:23: error: no template named 'is_same_v' in namespace 'std'; did you mean 'is_same'?
135 | (std::is_same_v<decltype(T().data()), const char*>
| ~~~~~^~~~~~~~~
| is_same
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/c++/v1/__type_traits/is_same.h:22:29: note: 'is_same' declared here
22 | struct _LIBCPP_TEMPLATE_VIS is_same : _BoolConstant<__is_same(_Tp, _Up)> {};
| ^
In file included from /Users/xxxxx/.phpbrew/build/php-8.1.32/ext/intl/intl_convertcpp.cpp:17:
In file included from /Users/xxxxx/.phpbrew/build/php-8.1.32/ext/intl/intl_convertcpp.h:22:
In file included from /opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/unistr.h:40:
/opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/stringpiece.h:140:17: error: use of address-of-label extension outside of a function body
140 | std::is_same_v<decltype(T().size()), size_t>>>
| ^
/opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/stringpiece.h:140:62: error: expected member name or ';' after declaration specifiers
140 | std::is_same_v<decltype(T().size()), size_t>>>
| ^
In file included from /Users/xxxxx/.phpbrew/build/php-8.1.32/ext/intl/intl_convertcpp.cpp:17:
In file included from /Users/xxxxx/.phpbrew/build/php-8.1.32/ext/intl/intl_convertcpp.h:22:
/opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/unistr.h:346:40: error: no template named 'enable_if_t' in namespace 'std'
346 | template<typename S, typename = std::enable_if_t<ConvertibleToU16StringView<S>>>
| ~~~~~^
/opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/unistr.h:381:40: error: no template named 'enable_if_t' in namespace 'std'
381 | template<typename S, typename = std::enable_if_t<ConvertibleToU16StringView<S>>>
| ~~~~~^
/opt/homebrew/Cellar/icu4c@77/77.1/include/unicode/unistr.h:1959:40: error: no template named 'enable_if_t' in namespace 'std'
1959 | template<typename S, typename = std::enable_if_t<ConvertibleToU16StringView<S>>>
| ~~~~~^
fatal error: too many errors emitted, stopping now [-ferror-limit=]
3 warnings and 20 errors generated.
I can PR a fix that adds environment variable support but I'd prefer if can get #1359 merged first as I've done it on top of that.