[libc] add LIBC_INLINE for expected, use CTAD in abs_timeout (llvm#94348)

Author: c8ef

libc/src/__support/CPP/expected.h

@@ -9,6 +9,8 @@
 #ifndef LLVM_LIBC_SRC___SUPPORT_CPP_EXPECTED_H
 #define LLVM_LIBC_SRC___SUPPORT_CPP_EXPECTED_H
 
+#include "src/__support/macros/attributes.h"
+
 namespace LIBC_NAMESPACE::cpp {
 
 // This is used to hold an unexpected value so that a different constructor is
@@ -17,10 +19,12 @@ template <class T> class unexpected {
   T value;
 
 public:
-  constexpr explicit unexpected(T value) : value(value) {}
-  constexpr T error() { return value; }
+  LIBC_INLINE constexpr explicit unexpected(T value) : value(value) {}
+  LIBC_INLINE constexpr T error() { return value; }
 };
 
+template <class T> explicit unexpected(T) -> unexpected<T>;
+
 template <class T, class E> class expected {
   union {
     T exp;
@@ -29,23 +33,23 @@ template <class T, class E> class expected {
   bool is_expected;
 
 public:
-  constexpr expected(T exp) : exp(exp), is_expected(true) {}
-  constexpr expected(unexpected<E> unexp)
+  LIBC_INLINE constexpr expected(T exp) : exp(exp), is_expected(true) {}
+  LIBC_INLINE constexpr expected(unexpected<E> unexp)
       : unexp(unexp.error()), is_expected(false) {}
 
-  constexpr bool has_value() const { return is_expected; }
+  LIBC_INLINE constexpr bool has_value() const { return is_expected; }
 
-  constexpr T &value() { return exp; }
-  constexpr E &error() { return unexp; }
-  constexpr const T &value() const { return exp; }
-  constexpr const E &error() const { return unexp; }
+  LIBC_INLINE constexpr T &value() { return exp; }
+  LIBC_INLINE constexpr E &error() { return unexp; }
+  LIBC_INLINE constexpr const T &value() const { return exp; }
+  LIBC_INLINE constexpr const E &error() const { return unexp; }
 
-  constexpr operator bool() const { return is_expected; }
+  LIBC_INLINE constexpr operator bool() const { return is_expected; }
 
-  constexpr T &operator*() { return exp; }
-  constexpr const T &operator*() const { return exp; }
-  constexpr T *operator->() { return &exp; }
-  constexpr const T *operator->() const { return &exp; }
+  LIBC_INLINE constexpr T &operator*() { return exp; }
+  LIBC_INLINE constexpr const T &operator*() const { return exp; }
+  LIBC_INLINE constexpr T *operator->() { return &exp; }
+  LIBC_INLINE constexpr const T *operator->() const { return &exp; }
 };
 
 } // namespace LIBC_NAMESPACE::cpp

libc/src/__support/time/linux/abs_timeout.h

@@ -33,12 +33,12 @@ class AbsTimeout {
   from_timespec(timespec ts, bool realtime) {
     using namespace time_units;
     if (ts.tv_nsec < 0 || ts.tv_nsec >= 1_s_ns)
-      return cpp::unexpected<Error>(Error::Invalid);
+      return cpp::unexpected(Error::Invalid);
 
     // POSIX allows tv_sec to be negative. We interpret this as an expired
     // timeout.
     if (ts.tv_sec < 0)
-      return cpp::unexpected<Error>(Error::BeforeEpoch);
+      return cpp::unexpected(Error::BeforeEpoch);
 
     return AbsTimeout{ts, realtime};
   }