[libc] Include time.h in baremetal targets

[petrhosek]

These types and conversion functions are used in embedded development.

Note that we cannot yet include other entrypoints such as asctime because src/time/time_utils.h unconditionally uses EOVERFLOW, which is only defined in POSIX and not in C standard. This issue is tracked by #85556.

[llvmbot]

@llvm/pr-subscribers-libc

Author: Petr Hosek (petrhosek)

Changes

These types and conversion functions are used in embedded development.

Note that we cannot include other entrypoints such such asctime because it unconditionally uses EOVERFLOW which is only defined in POSIX and not in C standard. This will need to be addressed first.

---

Full diff: https://github.com/llvm/llvm-project/pull/85026.diff

5 Files Affected:

• (modified) libc/config/baremetal/api.td (+9)
• (modified) libc/config/baremetal/arm/entrypoints.txt (+3)
• (modified) libc/config/baremetal/arm/headers.txt (+1)
• (modified) libc/config/baremetal/riscv/entrypoints.txt (+3)
• (modified) libc/config/baremetal/riscv/headers.txt (+1)

diff --git a/libc/config/baremetal/api.td b/libc/config/baremetal/api.td
index 80d0e0ba22ca51..e153c52a7b98cb 100644
--- a/libc/config/baremetal/api.td
+++ b/libc/config/baremetal/api.td
@@ -68,6 +68,15 @@ def StringAPI : PublicAPI<"string.h"> {
   let Types = ["size_t"];
 }
 
+def TimeAPI : PublicAPI<"time.h"> {
+  let Types = [
+    "clock_t",
+    "time_t",
+    "struct tm",
+    "struct timespec",
+  ];
+}
+
 def UCharAPI : PublicAPI<"uchar.h"> {
   let Types = ["mbstate_t"];
 }
diff --git a/libc/config/baremetal/arm/entrypoints.txt b/libc/config/baremetal/arm/entrypoints.txt
index 589ec5237e98da..fa5d12412ced28 100644
--- a/libc/config/baremetal/arm/entrypoints.txt
+++ b/libc/config/baremetal/arm/entrypoints.txt
@@ -180,6 +180,9 @@ set(TARGET_LIBC_ENTRYPOINTS
     libc.src.stdlib.strtoll
     libc.src.stdlib.strtoul
     libc.src.stdlib.strtoull
+
+    # time.h entrypoints
+    libc.src.time.difftime
 )
 
 set(TARGET_LIBM_ENTRYPOINTS
diff --git a/libc/config/baremetal/arm/headers.txt b/libc/config/baremetal/arm/headers.txt
index 962981f8a2087d..3608364e45bdeb 100644
--- a/libc/config/baremetal/arm/headers.txt
+++ b/libc/config/baremetal/arm/headers.txt
@@ -13,5 +13,6 @@ set(TARGET_PUBLIC_HEADERS
     libc.include.string
     libc.include.strings
     libc.include.sys_queue
+    libc.include.time
     libc.include.uchar
 )
diff --git a/libc/config/baremetal/riscv/entrypoints.txt b/libc/config/baremetal/riscv/entrypoints.txt
index 09de1b416e0e94..58624e8b250987 100644
--- a/libc/config/baremetal/riscv/entrypoints.txt
+++ b/libc/config/baremetal/riscv/entrypoints.txt
@@ -180,6 +180,9 @@ set(TARGET_LIBC_ENTRYPOINTS
     libc.src.stdlib.strtoll
     libc.src.stdlib.strtoul
     libc.src.stdlib.strtoull
+
+    # time.h entrypoints
+    libc.src.time.difftime
 )
 
 set(TARGET_LIBM_ENTRYPOINTS
diff --git a/libc/config/baremetal/riscv/headers.txt b/libc/config/baremetal/riscv/headers.txt
index 962981f8a2087d..3608364e45bdeb 100644
--- a/libc/config/baremetal/riscv/headers.txt
+++ b/libc/config/baremetal/riscv/headers.txt
@@ -13,5 +13,6 @@ set(TARGET_PUBLIC_HEADERS
     libc.include.string
     libc.include.strings
     libc.include.sys_queue
+    libc.include.time
     libc.include.uchar
 )

[nickdesaulniers]

Note that we cannot include other entrypoints such such asctime because it unconditionally uses EOVERFLOW which is only defined in POSIX and not in C standard. This will need to be addressed first.

Please file a bug.

[petrhosek]

Note that we cannot include other entrypoints such such asctime because it unconditionally uses EOVERFLOW which is only defined in POSIX and not in C standard. This will need to be addressed first.

Please file a bug.

Filed #85556.