ProcessorCount: Use ERROR_QUIET with execute_process (#11302)

Also, comment out all "debugging" calls to message() that helped
us interpret the output on other platforms when running on the
dashboard clients.

Using ERROR_QUIET avoids unnecessary stderr output while calling
external tools to determine the processor count. If there's an
error parsing the output, we set the count to 0 anyhow.

Also, the test will fail on a CMake dashboard run if the count
comes back equal to 0.

Now that the code is "done"-ish, remove the debugging output.
Expect no output on stdout or stderr when calling the
ProcessorCount function from now on.

1 files changed, 10 insertions, 3 deletions

diff --git a/Tests/CMakeTests/ProcessorCountTest.cmake.in b/Tests/CMakeTests/ProcessorCountTest.cmake.in
index c5feb315cf..98f6ab16df 100644
--- a/Tests/CMakeTests/ProcessorCountTest.cmake.in
+++ b/Tests/CMakeTests/ProcessorCountTest.cmake.in
@@ -1,14 +1,20 @@
 include(ProcessorCount)
 
 ProcessorCount(processor_count)
+
+message("### 1. This line should be the first line of text in the test output.")
+message("### 2. If there was output from this test before line #1, then the")
+message("### 3. ProcessorCount(...) function call is emitting output that it shouldn't...")
+
 message("processor_count='${processor_count}'")
 
 execute_process(
   COMMAND "@CMAKE_BINARY_DIR@/Source/kwsys/$ENV{CMAKE_CONFIG_TYPE}/cmsysTestsCxx"
   testSystemInformation
-  OUTPUT_VARIABLE out)
+  OUTPUT_VARIABLE tsi_out
+  ERROR_VARIABLE tsi_err)
 string(REGEX REPLACE "(.*)GetNumberOfPhysicalCPU:.([0-9]*)(.*)" "\\2"
-  system_info_processor_count "${out}")
+  system_info_processor_count "${tsi_out}")
 
 message("system_info_processor_count='${system_info_processor_count}'")
 
@@ -19,7 +25,8 @@ endif()
 message("")
 message("CTEST_FULL_OUTPUT (Avoid ctest truncation of output)")
 message("")
-message("out='${out}'")
+message("tsi_out='${tsi_out}'")
+message("tsi_err='${tsi_err}'")
 message("")
 
 # Evaluate possible error conditions: