CheckSourceRuns: do not fail on unrecognized arguments

The old `check_X_source_runs` modules did not verify the arguments, so
we cannot start doing it now. Downgrade the hard error introduced in
commit 357e2ef429 (CheckSoureRuns: Add a unified way to check if a
source runs, 2020-09-14) via !5223 into a noisy warning.

2 files changed, 17 insertions, 2 deletions

diff --git a/Tests/RunCMake/CheckSourceRuns/UnknownArgument-stderr.txt b/Tests/RunCMake/CheckSourceRuns/UnknownArgument-stderr.txt
index 9b576b5..6824e72 100644
--- a/Tests/RunCMake/CheckSourceRuns/UnknownArgument-stderr.txt
+++ b/Tests/RunCMake/CheckSourceRuns/UnknownArgument-stderr.txt
@@ -1,4 +1,17 @@
-^CMake Error at [^
+^CMake Warning \(dev\) at [^
+]*/Modules/Internal/CheckSourceRuns.cmake:[0-9]+ \(message\):
+  Unknown argument:
+
+    BAD
+
+Call Stack \(most recent call first\):
+  [^
+]*/Modules/CheckCSourceRuns.cmake:[0-9]+ \(cmake_check_source_runs\)
+  UnknownArgument.cmake:[0-9]+ \(check_c_source_runs\)
+  CMakeLists.txt:[0-9]+ \(include\)
+This warning is for project developers.  Use -Wno-dev to suppress it.
+
+CMake Error at [^
 ]*/Modules/Internal/CheckSourceRuns.cmake:[0-9]+ \(message\):
   Unknown argument:
 
diff --git a/Tests/RunCMake/CheckSourceRuns/UnknownArgument.cmake b/Tests/RunCMake/CheckSourceRuns/UnknownArgument.cmake
index 6e50fa7..927a6b0 100644
--- a/Tests/RunCMake/CheckSourceRuns/UnknownArgument.cmake
+++ b/Tests/RunCMake/CheckSourceRuns/UnknownArgument.cmake
@@ -1,5 +1,7 @@
 
 enable_language (C)
+include(CheckCSourceRuns)
 include(CheckSourceRuns)
 
-check_source_runs(C "int main() {return 0;}" SHOULD_BUILD SRC_EXT C BAD)
+check_c_source_runs("int main() {return 0;}" C_SHOULD_BUILD BAD)
+check_source_runs(C "int main() {return 0;}" SHOULD_BUILD SRC_EXT c BAD)