Merge topic 'try_compile-Makefile-config'

052c2ae Document CMAKE_TRY_COMPILE_CONFIGURATION variable
56efc60 Honor CMAKE_TRY_COMPILE_CONFIGURATION in Makefile generators (#10809)

4 files changed, 27 insertions, 2 deletions

diff --git a/Source/cmDocumentVariables.cxx b/Source/cmDocumentVariables.cxx
index 5dfa64e..e9b54d8 100644
--- a/Source/cmDocumentVariables.cxx
+++ b/Source/cmDocumentVariables.cxx
@@ -1121,6 +1121,14 @@ void cmDocumentVariables::DefineVariables(cmake* cm)
      "this variable for a target if they are set.  "
      "Library targets are otherwise placed in this directory.",false,
      "Variables that Control the Build");
+  cm->DefineProperty
+    ("CMAKE_TRY_COMPILE_CONFIGURATION", cmProperty::VARIABLE,
+     "Build configuration used for try_compile and try_run projects.",
+     "Projects built by try_compile and try_run are built "
+     "synchronously during the CMake configuration step.  "
+     "Therefore a specific build configuration must be chosen even "
+     "if the generated build system supports multiple configurations.",false,
+     "Variables that Control the Build");
 
 
 //   Variables defined when the a language is enabled These variables will
diff --git a/Source/cmMakefile.cxx b/Source/cmMakefile.cxx
index 41d36dc..e1cea22 100644
--- a/Source/cmMakefile.cxx
+++ b/Source/cmMakefile.cxx
@@ -2718,6 +2718,18 @@ int cmMakefile::TryCompile(const char *srcdir, const char *bindir,
   cm.SetStartOutputDirectory(bindir);
   cm.SetCMakeCommand(cmakeCommand.c_str());
   cm.LoadCache();
+  if(!gg->IsMultiConfig())
+    {
+    if(const char* config =
+       this->GetDefinition("CMAKE_TRY_COMPILE_CONFIGURATION"))
+      {
+      // Tell the single-configuration generator which one to use.
+      // Add this before the user-provided CMake arguments in case
+      // one of the arguments is -DCMAKE_BUILD_TYPE=...
+      cm.AddCacheEntry("CMAKE_BUILD_TYPE", config,
+                       "Build configuration", cmCacheManager::STRING);
+      }
+    }
   // if cmake args were provided then pass them in
   if (cmakeArgs)
     {
diff --git a/Source/cmTryCompileCommand.h b/Source/cmTryCompileCommand.h
index 5b4ffca..0c67a8b 100644
--- a/Source/cmTryCompileCommand.h
+++ b/Source/cmTryCompileCommand.h
@@ -99,7 +99,9 @@ public:
       "Return the success or failure in "
       "RESULT_VAR. CMAKE_FLAGS can be used to pass -DVAR:TYPE=VALUE flags "
       "to the cmake that is run during the build. "
-      "";
+      "Set variable CMAKE_TRY_COMPILE_CONFIGURATION to choose a build "
+      "configuration."
+      ;
     }
   
   cmTypeMacro(cmTryCompileCommand, cmCoreTryCompile);
diff --git a/Source/cmTryRunCommand.h b/Source/cmTryRunCommand.h
index ca48e90..f86d863 100644
--- a/Source/cmTryRunCommand.h
+++ b/Source/cmTryRunCommand.h
@@ -93,7 +93,10 @@ public:
       "that when crosscompiling, the cache variables will have to be set "
       "manually to the output of the executable. You can also \"guard\" the "
       "calls to try_run with if(CMAKE_CROSSCOMPILING) and provide an "
-      "easy-to-preset alternative for this case.\n";
+      "easy-to-preset alternative for this case.\n"
+      "Set variable CMAKE_TRY_COMPILE_CONFIGURATION to choose a build "
+      "configuration."
+      ;
     }
 
   cmTypeMacro(cmTryRunCommand, cmCoreTryCompile);