fix cppstd checks for c++26 in newer compiler versions (#17250)

* fix cppstd checks for c++26 in newer compiler versions

* more tests

* Conan 2.9.1

---------

Co-authored-by: czoido <mrgalleta@gmail.com>

conan/tools/build/cppstd.py

@@ -164,8 +164,14 @@ def _apple_clang_supported_cppstd(version):
         return ["98", "gnu98", "11", "gnu11", "14", "gnu14", "17", "gnu17"]
     if version < "13.0":
         return ["98", "gnu98", "11", "gnu11", "14", "gnu14", "17", "gnu17", "20", "gnu20"]
+    # https://github.com/conan-io/conan/pull/17092 doesn't show c++23 full support until 16
+    # but it was this before Conan 2.9, so keeping it to not break
+    if version < "16.0":
+        return ["98", "gnu98", "11", "gnu11", "14", "gnu14", "17", "gnu17", "20", "gnu20",
+                "23", "gnu23"]
 
-    return ["98", "gnu98", "11", "gnu11", "14", "gnu14", "17", "gnu17", "20", "gnu20", "23", "gnu23"]
+    return ["98", "gnu98", "11", "gnu11", "14", "gnu14", "17", "gnu17", "20", "gnu20", "23", "gnu23",
+            "26", "gnu26"]
 
 
 def _gcc_supported_cppstd(version):
@@ -184,8 +190,13 @@ def _gcc_supported_cppstd(version):
         return ["98", "gnu98", "11", "gnu11", "14", "gnu14", "17", "gnu17"]
     if version < "11":
         return ["98", "gnu98", "11", "gnu11", "14", "gnu14", "17", "gnu17", "20", "gnu20"]
+    # https://github.com/conan-io/conan/pull/17092
+    if version < "14.0":
+        return ["98", "gnu98", "11", "gnu11", "14", "gnu14", "17", "gnu17", "20", "gnu20",
+                "23", "gnu23"]
 
-    return ["98", "gnu98", "11", "gnu11", "14", "gnu14", "17", "gnu17", "20", "gnu20", "23", "gnu23"]
+    return ["98", "gnu98", "11", "gnu11", "14", "gnu14", "17", "gnu17", "20", "gnu20", "23", "gnu23",
+            "26", "gnu26"]
 
 
 def _msvc_supported_cppstd(version):
@@ -222,8 +233,12 @@ def _clang_supported_cppstd(version):
         return ["98", "gnu98", "11", "gnu11", "14", "gnu14", "17", "gnu17"]
     if version < "12":
         return ["98", "gnu98", "11", "gnu11", "14", "gnu14", "17", "gnu17", "20", "gnu20"]
-
-    return ["98", "gnu98", "11", "gnu11", "14", "gnu14", "17", "gnu17", "20", "gnu20", "23", "gnu23"]
+    # https://github.com/conan-io/conan/pull/17092
+    if version < "17.0":
+        return ["98", "gnu98", "11", "gnu11", "14", "gnu14", "17", "gnu17", "20", "gnu20",
+                "23", "gnu23"]
+    return ["98", "gnu98", "11", "gnu11", "14", "gnu14", "17", "gnu17", "20", "gnu20", "23", "gnu23",
+            "26", "gnu26"]
 
 
 def _mcst_lcc_supported_cppstd(version):

conans/__init__.py

@@ -1,4 +1,4 @@
 CHECKSUM_DEPLOY = "checksum_deploy"  # Only when v2
 REVISIONS = "revisions"  # Only when enabled in config, not by default look at server_launcher.py
 
-__version__ = '2.9.0'
+__version__ = '2.9.1'

test/integration/configuration/test_profile_plugin.py

@@ -27,6 +27,17 @@ def test_remove_plugin_file(self):
         c.run("profile show", assert_error=True)
         assert "ERROR: The 'profile.py' plugin file doesn't exist" in c.out
 
+    def test_regresion_29(self):
+        # https://github.com/conan-io/conan/issues/17247
+        c = TestClient()
+        c.save({"conanfile.txt": ""})
+        c.run("install . -s compiler=clang -s compiler.version=19 -s compiler.cppstd=26")
+        # doesn't fail anymore
+        c.run("install . -s compiler=apple-clang -s compiler.version=16 -s compiler.cppstd=26")
+        # doesn't fail anymore
+        c.run("install . -s compiler=gcc -s compiler.version=14 -s compiler.cppstd=26")
+        # doesn't fail anymore
+
 
 def test_android_ndk_version():
     c = TestClient()