[rust][tools] Fix Rust build example configuration handling

Improve the Rust build integration across core, applications, components, and module examples. Fix build failure propagation, target and feature handling, linker flags, example configuration semantics, and add STM32 CI attach coverage.

7 files changed, 64 insertions, 34 deletions

diff --git a/components/rust/examples/application/SConscript b/components/rust/examples/application/SConscript
index c6c4de3db8..fc50bc2825 100644
--- a/components/rust/examples/application/SConscript
+++ b/components/rust/examples/application/SConscript
@@ -6,7 +6,7 @@ cwd = GetCurrentDir()
 
 # Import usrapp build module and build support
 sys.path.append(os.path.join(cwd, '../../tools'))
-from build_usrapp import build_example_usrapp
+from build_usrapp import UserAppBuildError, build_example_usrapp
 from build_support import clean_rust_build
 
 
@@ -31,7 +31,7 @@ def load_extended_feature_configs():
 
 group = []
 
-if not _has('RT_RUST_BUILD_APPLICATIONS'):
+if not (_has('RT_RUST_BUILD_APPLICATIONS') or _has('RT_RUST_BUILD_ALL_EXAMPLES')) and not GetOption('clean'):
     Return('group')
 
 # Load extended feature configurations
@@ -51,12 +51,16 @@ if GetOption('clean'):
         print('No example_usrapp build artifacts to clean')
 else:
     import rtconfig
-    LIBS, LIBPATH, LINKFLAGS = build_example_usrapp(
-        cwd=cwd,
-        has_func=_has,
-        rtconfig=rtconfig,
-        build_root=os.path.join(Dir('#').abspath, "build", "example_usrapp")
-    )
+    try:
+        LIBS, LIBPATH, LINKFLAGS = build_example_usrapp(
+            cwd=cwd,
+            has_func=_has,
+            rtconfig=rtconfig,
+            build_root=os.path.join(Dir('#').abspath, "build", "example_usrapp")
+        )
+    except UserAppBuildError as e:
+        print(f'Error: {e}')
+        sys.exit(1)
 
 group = DefineGroup(
     'example_usrapp', 
@@ -67,4 +71,4 @@ group = DefineGroup(
     LINKFLAGS=LINKFLAGS
 )
 
-Return('group')
\ No newline at end of file
+Return('group')
diff --git a/components/rust/examples/application/fs/Cargo.toml b/components/rust/examples/application/fs/Cargo.toml
index 2556b5f0a4..40c2e01ffa 100644
--- a/components/rust/examples/application/fs/Cargo.toml
+++ b/components/rust/examples/application/fs/Cargo.toml
@@ -12,6 +12,6 @@ default = []
 enable-log = ["em_component_log/enable-log"]
 
 [dependencies]
-rt-rust = { path = "../../../core" }
+rt-rust = { path = "../../../core", features = ["fs"] }
 rt_macros = { path = "../../../rt_macros" }
-em_component_log = { path = "../../component/log"}
\ No newline at end of file
+em_component_log = { path = "../../component/log"}
diff --git a/components/rust/examples/application/loadlib/Cargo.toml b/components/rust/examples/application/loadlib/Cargo.toml
index 1e1065f91a..66c7abfb91 100644
--- a/components/rust/examples/application/loadlib/Cargo.toml
+++ b/components/rust/examples/application/loadlib/Cargo.toml
@@ -8,5 +8,5 @@ name = "em_loadlib"
 crate-type = ["staticlib"]
 
 [dependencies]
-rt-rust = { path = "../../../core" }
-rt_macros = { path = "../../../rt_macros" }
\ No newline at end of file
+rt-rust = { path = "../../../core", features = ["libdl"] }
+rt_macros = { path = "../../../rt_macros" }
diff --git a/components/rust/examples/component/SConscript b/components/rust/examples/component/SConscript
index 40d11c0446..ccfa01673b 100644
--- a/components/rust/examples/component/SConscript
+++ b/components/rust/examples/component/SConscript
@@ -6,7 +6,7 @@ cwd = GetCurrentDir()
 
 # Import component build module and build support
 sys.path.append(os.path.join(cwd, '../../tools'))
-from build_component import build_example_component
+from build_component import ComponentBuildError, build_example_component
 from build_support import clean_rust_build
 
 # Load feature configurations
@@ -25,12 +25,11 @@ def _has(sym: str) -> bool:
         return bool(GetDepend(sym))
 
 
-# Early return if Rust or log component is not enabled
-if not _has('RT_USING_RUST'):
+if not _has('RT_USING_RUST') and not GetOption('clean'):
     group = []
     Return('group')
 
-if not _has('RUST_LOG_COMPONENT'):
+if not (_has('RT_RUST_BUILD_COMPONENTS') or _has('RT_RUST_BUILD_ALL_EXAMPLES')) and not GetOption('clean'):
     group = []
     Return('group')
 
@@ -51,12 +50,16 @@ if GetOption('clean'):
 else:
     # Build the component using the extracted build module
     import rtconfig
-    LIBS, LIBPATH, LINKFLAGS = build_example_component(
-        cwd=cwd,
-        has_func=_has,
-        rtconfig=rtconfig,
-        build_root=os.path.join(Dir('#').abspath, "build", "example_component")
-    )
+    try:
+        LIBS, LIBPATH, LINKFLAGS = build_example_component(
+            cwd=cwd,
+            has_func=_has,
+            rtconfig=rtconfig,
+            build_root=os.path.join(Dir('#').abspath, "build", "example_component")
+        )
+    except ComponentBuildError as e:
+        print(f'Error: {e}')
+        sys.exit(1)
 
 # Define component group for SCons
 group = DefineGroup(
@@ -68,4 +71,4 @@ group = DefineGroup(
     LINKFLAGS=LINKFLAGS
 )
 
-Return('group')
\ No newline at end of file
+Return('group')
diff --git a/components/rust/examples/modules/SConscript b/components/rust/examples/modules/SConscript
index 98e57d1fd9..056501c057 100644
--- a/components/rust/examples/modules/SConscript
+++ b/components/rust/examples/modules/SConscript
@@ -32,6 +32,20 @@ def _has(sym: str) -> bool:
     except Exception:
         return bool(GetDepend(sym))
 
+
+MODULE_CONFIG_MAP = {
+    'example_lib': 'RT_RUST_MODULE_SIMPLE_MODULE',
+}
+
+
+def should_build_module(module_dir: str) -> bool:
+    if _has('RT_RUST_BUILD_ALL_EXAMPLES'):
+        return True
+
+    config = MODULE_CONFIG_MAP.get(os.path.basename(module_dir))
+    return bool(config and _has(config))
+
+
 def detect_target_for_dynamic_modules():
     """
     Detect the appropriate Rust target for dynamic modules.
@@ -68,7 +82,7 @@ def build_rust_module(module_dir, build_root):
         cargo_config = toml.load(f)
     
     module_name = cargo_config['package']['name']
-    
+
     # Detect target automatically based on the current configuration
     target = detect_target_for_dynamic_modules()
     print(f"Building Rust module '{module_name}' for target: {target}")
@@ -121,7 +135,12 @@ def build_rust_module(module_dir, build_root):
         return [], [], ""
 
 # Check dependencies
-if not _has('RT_RUST_BUILD_MODULES'):
+if not _has('RT_USING_MODULE') and not GetOption('clean'):
+    Return([])
+
+if not (
+    _has('RT_RUST_BUILD_MODULES') or _has('RT_RUST_BUILD_ALL_EXAMPLES')
+) and not GetOption('clean'):
     Return([])
 
 build_root = os.path.join(Dir('#').abspath, "build", "rust_modules")
@@ -142,7 +161,11 @@ else:
     modules_built = []
     for item in os.listdir(cwd):
         item_path = os.path.join(cwd, item)
-        if os.path.isdir(item_path) and os.path.exists(os.path.join(item_path, 'Cargo.toml')):
+        if (
+            os.path.isdir(item_path)
+            and os.path.exists(os.path.join(item_path, 'Cargo.toml'))
+            and should_build_module(item_path)
+        ):
             result = build_rust_module(item_path, build_root)
             if result[0]:
                 modules_built.extend(result[0])
@@ -151,9 +174,9 @@ else:
         print(f"Successfully built {len(modules_built)} Rust dynamic module(s): {', '.join(modules_built)}")
 
 group = DefineGroup(
-    'rust_modules', 
-    [], 
-    depend=['RT_RUST_BUILD_MODULES']
+    'rust_modules',
+    [],
+    depend=['RT_USING_RUST']
 )
 
-Return('group')
\ No newline at end of file
+Return('group')
diff --git a/components/rust/examples/modules/example_lib/Cargo.toml b/components/rust/examples/modules/example_lib/Cargo.toml
index e44aae2848..6a490acad8 100644
--- a/components/rust/examples/modules/example_lib/Cargo.toml
+++ b/components/rust/examples/modules/example_lib/Cargo.toml
@@ -9,4 +9,4 @@ edition = "2024"
 crate-type = ["cdylib"]
 
 [dependencies]
-rt-rust = { path = "../../.." }
\ No newline at end of file
+rt-rust = { path = "../../../core" }
\ No newline at end of file
diff --git a/components/rust/examples/modules/example_lib/src/lib.rs b/components/rust/examples/modules/example_lib/src/lib.rs
index 79fe384e6a..8b86c593cd 100644
--- a/components/rust/examples/modules/example_lib/src/lib.rs
+++ b/components/rust/examples/modules/example_lib/src/lib.rs
@@ -11,7 +11,7 @@
 /* Bring rt-rust's println! macro into scope */ 
 use rt_rust::println;
 use core::ffi::{c_char, CStr};
-#[no_mangle]
+#[unsafe(no_mangle)]
 pub extern "C" fn rust_mylib_println(s: *const c_char) {
     if s.is_null() {
         println!("");
@@ -24,7 +24,7 @@ pub extern "C" fn rust_mylib_println(s: *const c_char) {
     }
 }
 
-#[no_mangle]
+#[unsafe(no_mangle)]
 pub extern "C" fn rust_mylib_add(a: usize, b: usize) -> usize {
     a + b
 }