Stop automatically adding warning flags and -Werror.

It's better to be lax for normal users trying to build the puzzles
from source to actually run them. That way, warning changes in some
particular compiler I haven't seen yet won't break the build.

Instead, I've invented a cmake setting -DSTRICT=ON which turns on all
those flags. So I can build with them myself, to ensure the code is as
portable as possible. And that flag is set in Buildscr, so that my
official builds won't complete until that warning mode is satisfied.

2 files changed, 8 insertions, 19 deletions

diff --git a/Buildscr b/Buildscr
index 69cc2d0..29d4e56 100644
--- a/Buildscr
+++ b/Buildscr
@@ -26,7 +26,11 @@ in puzzles do perl -i -pe 's/Unidentified build/$(Version)/' osx/Info.plist
 
 ifneq "$(NOICONS)" yes then
   # Run enough of a native Unix build to produce the various icons.
-  in . do cmake -B build-icons puzzles
+  # This also checks that the build completes in 'strict' mode (with
+  # lots of warnings and -Werror), and triggers a build failure if
+  # not.
+  in . do cmake -B build-icons puzzles -DSTRICT=ON
+  in build-icons do make -j$(nproc)
   in build-icons do make -j$(nproc) icons VERBOSE=1
 
   # Copy the C icon files into the icons source subdirectory, for the
diff --git a/cmake/platforms/unix.cmake b/cmake/platforms/unix.cmake
index b858be8..df95144 100644
--- a/cmake/platforms/unix.cmake
+++ b/cmake/platforms/unix.cmake
@@ -29,24 +29,9 @@ set(platform_libs -lm)
 
 set(build_icons TRUE)
 
-function(try_append_cflag flag)
-  set(CMAKE_TRY_COMPILE_TARGET_TYPE STATIC_LIBRARY)
-  set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${flag}")
-  try_compile(compile_passed ${CMAKE_BINARY_DIR}
-    SOURCES ${CMAKE_SOURCE_DIR}/cmake/testbuild.c
-    OUTPUT_VARIABLE test_compile_output
-    CMAKE_FLAGS "-DINCLUDE_DIRECTORIES=${GTK_INCLUDE_DIRS}")
-  if(compile_passed)
-    set(CMAKE_C_FLAGS ${CMAKE_C_FLAGS} PARENT_SCOPE)
-  endif()
-endfunction()
-if (CMAKE_C_COMPILER_ID MATCHES "GNU" OR
-    CMAKE_C_COMPILER_ID MATCHES "Clang")
-  try_append_cflag(-Wall)
-  try_append_cflag(-Werror)
-  try_append_cflag(-std=c89)
-  try_append_cflag(-pedantic)
-  try_append_cflag(-Wwrite-strings)
+if(DEFINED STRICT AND (CMAKE_C_COMPILER_ID MATCHES "GNU" OR
+                       CMAKE_C_COMPILER_ID MATCHES "Clang"))
+  set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -Wwrite-strings -std=c99 -pedantic -Werror")
 endif()
 
 function(get_platform_puzzle_extra_source_files OUTVAR NAME)