Add the WriteCompilerDetectionHeader module.

Provide a function to write a portable header to detect compiler
features.  Generate a preprocessor #error for unknown compilers
and compiler versions whose features are not yet recorded.  This
error condition might be relaxed in the future, but for now it
is useful for verification of expectations.

33 files changed, 174 insertions, 0 deletions

diff --git a/Tests/RunCMake/CMakeLists.txt b/Tests/RunCMake/CMakeLists.txt
index e797a73..7f6ebf1 100644
--- a/Tests/RunCMake/CMakeLists.txt
+++ b/Tests/RunCMake/CMakeLists.txt
@@ -54,6 +54,7 @@ add_RunCMake_test(TargetObjects)
 add_RunCMake_test(TargetSources)
 add_RunCMake_test(find_dependency)
 add_RunCMake_test(CompileFeatures)
+add_RunCMake_test(WriteCompilerDetectionHeader)
 if(NOT WIN32)
   add_RunCMake_test(PositionIndependentCode)
   set(SKIP_VISIBILITY 0)
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/CMakeLists.txt b/Tests/RunCMake/WriteCompilerDetectionHeader/CMakeLists.txt
new file mode 100644
index 0000000..872338d
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/CMakeLists.txt
@@ -0,0 +1,3 @@
+cmake_minimum_required(VERSION 3.0)
+project(${RunCMake_TEST} CXX)
+include(${RunCMake_TEST}.cmake NO_POLICY_SCOPE)
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/ExtraArgs-result.txt b/Tests/RunCMake/WriteCompilerDetectionHeader/ExtraArgs-result.txt
new file mode 100644
index 0000000..d00491f
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/ExtraArgs-result.txt
@@ -0,0 +1 @@
+1
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/ExtraArgs-stderr.txt b/Tests/RunCMake/WriteCompilerDetectionHeader/ExtraArgs-stderr.txt
new file mode 100644
index 0000000..62c4ff1
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/ExtraArgs-stderr.txt
@@ -0,0 +1,5 @@
+CMake Error at .*Modules/WriteCompilerDetectionHeader.cmake:[0-9]+ \(message\):
+  Unparsed arguments: GarbageArg
+Call Stack \(most recent call first\):
+  ExtraArgs.cmake:4 \(write_compiler_detection_header\)
+  CMakeLists.txt:3 \(include\)
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/ExtraArgs.cmake b/Tests/RunCMake/WriteCompilerDetectionHeader/ExtraArgs.cmake
new file mode 100644
index 0000000..c2a21af
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/ExtraArgs.cmake
@@ -0,0 +1,10 @@
+
+include(WriteCompilerDetectionHeader)
+
+write_compiler_detection_header(
+  FILE "${CMAKE_CURRENT_BINARY_DIR}/somefile"
+  PREFIX Pref
+  GarbageArg
+  COMPILERS GNU
+  FEATURES cxx_final
+)
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/FileTypo-result.txt b/Tests/RunCMake/WriteCompilerDetectionHeader/FileTypo-result.txt
new file mode 100644
index 0000000..d00491f
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/FileTypo-result.txt
@@ -0,0 +1 @@
+1
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/FileTypo-stderr.txt b/Tests/RunCMake/WriteCompilerDetectionHeader/FileTypo-stderr.txt
new file mode 100644
index 0000000..3c0c076
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/FileTypo-stderr.txt
@@ -0,0 +1,5 @@
+CMake Error at .*Modules/WriteCompilerDetectionHeader.cmake:[0-9]+ \(message\):
+  write_compiler_detection_header: FILE parameter missing.
+Call Stack \(most recent call first\):
+  FileTypo.cmake:4 \(write_compiler_detection_header\)
+  CMakeLists.txt:3 \(include\)
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/FileTypo.cmake b/Tests/RunCMake/WriteCompilerDetectionHeader/FileTypo.cmake
new file mode 100644
index 0000000..c90eda2
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/FileTypo.cmake
@@ -0,0 +1,7 @@
+
+include(WriteCompilerDetectionHeader)
+
+write_compiler_detection_header(
+  FILE_TYPO "${CMAKE_CURRENT_BINARY_DIR}/somefile"
+  PREFIX Pref
+)
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidArgs-result.txt b/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidArgs-result.txt
new file mode 100644
index 0000000..d00491f
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidArgs-result.txt
@@ -0,0 +1 @@
+1
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidArgs-stderr.txt b/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidArgs-stderr.txt
new file mode 100644
index 0000000..b4d7e08
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidArgs-stderr.txt
@@ -0,0 +1,11 @@
+CMake Error at InvalidArgs.cmake:4 \(write_compiler_detection_header\):
+  write_compiler_detection_header Function invoked with incorrect arguments
+  for function named: write_compiler_detection_header
+Call Stack \(most recent call first\):
+  CMakeLists.txt:3 \(include\)
++
+CMake Error at InvalidArgs.cmake:6 \(write_compiler_detection_header\):
+  write_compiler_detection_header Function invoked with incorrect arguments
+  for function named: write_compiler_detection_header
+Call Stack \(most recent call first\):
+  CMakeLists.txt:3 \(include\)
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidArgs.cmake b/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidArgs.cmake
new file mode 100644
index 0000000..cfebae1
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidArgs.cmake
@@ -0,0 +1,6 @@
+
+include(WriteCompilerDetectionHeader)
+
+write_compiler_detection_header()
+
+write_compiler_detection_header(FILE)
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidCXXFeature-result.txt b/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidCXXFeature-result.txt
new file mode 100644
index 0000000..d00491f
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidCXXFeature-result.txt
@@ -0,0 +1 @@
+1
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidCXXFeature-stderr.txt b/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidCXXFeature-stderr.txt
new file mode 100644
index 0000000..f34c9e1
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidCXXFeature-stderr.txt
@@ -0,0 +1,5 @@
+CMake Error at .*Modules/WriteCompilerDetectionHeader.cmake:[0-9]+ \(message\):
+  Unsupported feature cxx_not_a_feature.
+Call Stack \(most recent call first\):
+  InvalidCXXFeature.cmake:4 \(write_compiler_detection_header\)
+  CMakeLists.txt:3 \(include\)
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidCXXFeature.cmake b/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidCXXFeature.cmake
new file mode 100644
index 0000000..da870fa
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidCXXFeature.cmake
@@ -0,0 +1,10 @@
+
+include(WriteCompilerDetectionHeader)
+
+write_compiler_detection_header(
+    FILE "${CMAKE_CURRENT_BINARY_DIR}/somefile"
+    PREFIX PREF_
+    COMPILERS GNU
+    FEATURES cxx_not_a_feature
+    VERSION 3.1
+)
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidCompiler-result.txt b/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidCompiler-result.txt
new file mode 100644
index 0000000..d00491f
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidCompiler-result.txt
@@ -0,0 +1 @@
+1
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidCompiler-stderr.txt b/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidCompiler-stderr.txt
new file mode 100644
index 0000000..f35f9f9
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidCompiler-stderr.txt
@@ -0,0 +1,5 @@
+CMake Error at .*Modules/WriteCompilerDetectionHeader.cmake:[0-9]+ \(message\):
+  Unsupported compiler NOT_A_COMPILER.
+Call Stack \(most recent call first\):
+  InvalidCompiler.cmake:4 \(write_compiler_detection_header\)
+  CMakeLists.txt:3 \(include\)
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidCompiler.cmake b/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidCompiler.cmake
new file mode 100644
index 0000000..ecd0957
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidCompiler.cmake
@@ -0,0 +1,10 @@
+
+include(WriteCompilerDetectionHeader)
+
+write_compiler_detection_header(
+    FILE "${CMAKE_CURRENT_BINARY_DIR}/somefile"
+    PREFIX PREF_
+    COMPILERS NOT_A_COMPILER
+    FEATURES cxx_final
+    VERSION 3.1
+)
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidFeature-result.txt b/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidFeature-result.txt
new file mode 100644
index 0000000..d00491f
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidFeature-result.txt
@@ -0,0 +1 @@
+1
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidFeature-stderr.txt b/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidFeature-stderr.txt
new file mode 100644
index 0000000..0445744
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidFeature-stderr.txt
@@ -0,0 +1,5 @@
+CMake Error at .*Modules/WriteCompilerDetectionHeader.cmake:[0-9]+ \(message\):
+  Unsupported feature not_a_feature.
+Call Stack \(most recent call first\):
+  InvalidFeature.cmake:4 \(write_compiler_detection_header\)
+  CMakeLists.txt:3 \(include\)
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidFeature.cmake b/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidFeature.cmake
new file mode 100644
index 0000000..cd83968
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/InvalidFeature.cmake
@@ -0,0 +1,10 @@
+
+include(WriteCompilerDetectionHeader)
+
+write_compiler_detection_header(
+    FILE "${CMAKE_CURRENT_BINARY_DIR}/somefile"
+    PREFIX PREF_
+    COMPILERS GNU
+    FEATURES not_a_feature
+    VERSION 3.1
+)
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/NoCompiler-result.txt b/Tests/RunCMake/WriteCompilerDetectionHeader/NoCompiler-result.txt
new file mode 100644
index 0000000..d00491f
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/NoCompiler-result.txt
@@ -0,0 +1 @@
+1
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/NoCompiler-stderr.txt b/Tests/RunCMake/WriteCompilerDetectionHeader/NoCompiler-stderr.txt
new file mode 100644
index 0000000..9451348
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/NoCompiler-stderr.txt
@@ -0,0 +1,6 @@
+CMake Error at .*Modules/WriteCompilerDetectionHeader.cmake:[0-9]+ \(message\):
+  Invalid arguments.  write_compiler_detection_header requires at least one
+  compiler.
+Call Stack \(most recent call first\):
+  NoCompiler.cmake:4 \(write_compiler_detection_header\)
+  CMakeLists.txt:3 \(include\)
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/NoCompiler.cmake b/Tests/RunCMake/WriteCompilerDetectionHeader/NoCompiler.cmake
new file mode 100644
index 0000000..2dc14e9
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/NoCompiler.cmake
@@ -0,0 +1,10 @@
+
+include(WriteCompilerDetectionHeader)
+
+write_compiler_detection_header(
+    FILE "${CMAKE_CURRENT_BINARY_DIR}/somefile"
+    PREFIX PREF_
+    # COMPILERS
+    FEATURES cxx_final
+    VERSION 3.1
+)
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/NoFeature-result.txt b/Tests/RunCMake/WriteCompilerDetectionHeader/NoFeature-result.txt
new file mode 100644
index 0000000..d00491f
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/NoFeature-result.txt
@@ -0,0 +1 @@
+1
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/NoFeature-stderr.txt b/Tests/RunCMake/WriteCompilerDetectionHeader/NoFeature-stderr.txt
new file mode 100644
index 0000000..193f297
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/NoFeature-stderr.txt
@@ -0,0 +1,6 @@
+CMake Error at .*Modules/WriteCompilerDetectionHeader.cmake:[0-9]+ \(message\):
+  Invalid arguments.  write_compiler_detection_header requires at least one
+  feature.
+Call Stack \(most recent call first\):
+  NoFeature.cmake:4 \(write_compiler_detection_header\)
+  CMakeLists.txt:3 \(include\)
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/NoFeature.cmake b/Tests/RunCMake/WriteCompilerDetectionHeader/NoFeature.cmake
new file mode 100644
index 0000000..1fbc129
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/NoFeature.cmake
@@ -0,0 +1,10 @@
+
+include(WriteCompilerDetectionHeader)
+
+write_compiler_detection_header(
+    FILE "${CMAKE_CURRENT_BINARY_DIR}/somefile"
+    PREFIX PREF_
+    COMPILERS GNU
+    # FEATURES
+    VERSION 3.1
+)
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/OldVersion-result.txt b/Tests/RunCMake/WriteCompilerDetectionHeader/OldVersion-result.txt
new file mode 100644
index 0000000..d00491f
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/OldVersion-result.txt
@@ -0,0 +1 @@
+1
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/OldVersion-stderr.txt b/Tests/RunCMake/WriteCompilerDetectionHeader/OldVersion-stderr.txt
new file mode 100644
index 0000000..842eb3f
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/OldVersion-stderr.txt
@@ -0,0 +1,5 @@
+CMake Error at .*Modules/WriteCompilerDetectionHeader.cmake:[0-9]+ \(message\):
+  VERSION parameter too low.
+Call Stack \(most recent call first\):
+  OldVersion.cmake:4 \(write_compiler_detection_header\)
+  CMakeLists.txt:3 \(include\)
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/OldVersion.cmake b/Tests/RunCMake/WriteCompilerDetectionHeader/OldVersion.cmake
new file mode 100644
index 0000000..a6e3022
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/OldVersion.cmake
@@ -0,0 +1,10 @@
+
+include(WriteCompilerDetectionHeader)
+
+write_compiler_detection_header(
+  FILE "${CMAKE_CURRENT_BINARY_DIR}/somefile"
+  PREFIX Pref
+  VERSION 3.0
+  COMPILERS GNU
+  FEATURES cxx_final
+)
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/PrefixTypo-result.txt b/Tests/RunCMake/WriteCompilerDetectionHeader/PrefixTypo-result.txt
new file mode 100644
index 0000000..d00491f
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/PrefixTypo-result.txt
@@ -0,0 +1 @@
+1
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/PrefixTypo-stderr.txt b/Tests/RunCMake/WriteCompilerDetectionHeader/PrefixTypo-stderr.txt
new file mode 100644
index 0000000..5fdcdb8
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/PrefixTypo-stderr.txt
@@ -0,0 +1,5 @@
+CMake Error at .*Modules/WriteCompilerDetectionHeader.cmake:[0-9]+ \(message\):
+  write_compiler_detection_header: PREFIX parameter missing.
+Call Stack \(most recent call first\):
+  PrefixTypo.cmake:4 \(write_compiler_detection_header\)
+  CMakeLists.txt:3 \(include\)
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/PrefixTypo.cmake b/Tests/RunCMake/WriteCompilerDetectionHeader/PrefixTypo.cmake
new file mode 100644
index 0000000..8b6774c
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/PrefixTypo.cmake
@@ -0,0 +1,7 @@
+
+include(WriteCompilerDetectionHeader)
+
+write_compiler_detection_header(
+  FILE "${CMAKE_CURRENT_BINARY_DIR}/somefile"
+  PREFIX_TYPO Pref
+)
diff --git a/Tests/RunCMake/WriteCompilerDetectionHeader/RunCMakeTest.cmake b/Tests/RunCMake/WriteCompilerDetectionHeader/RunCMakeTest.cmake
new file mode 100644
index 0000000..be79d41
--- /dev/null
+++ b/Tests/RunCMake/WriteCompilerDetectionHeader/RunCMakeTest.cmake
@@ -0,0 +1,12 @@
+include(RunCMake)
+
+run_cmake(InvalidArgs)
+run_cmake(NoCompiler)
+run_cmake(NoFeature)
+run_cmake(FileTypo)
+run_cmake(PrefixTypo)
+run_cmake(ExtraArgs)
+run_cmake(OldVersion)
+run_cmake(InvalidCompiler)
+run_cmake(InvalidFeature)
+run_cmake(InvalidCXXFeature)