Merge bitcoin-core/secp256k1#1532: cmake: Disable eager MSan in ctime_tests

f55703ba49 autotools: Delete unneeded compiler test (Hennadii Stepanov)
396e885886 autotools: Align MSan checking code with CMake's implementation (Hennadii Stepanov)
abde59f52d cmake: Report more compiler details in summary (Hennadii Stepanov)
7abf979a43 cmake: Disable `ctime_tests` if build with `-fsanitize=memory` (Hennadii Stepanov)

Pull request description:

  Same as https://github.com/bitcoin-core/secp256k1/pull/1517, but for the CMakle build system.

  The second commit improves the configure summary (similar to https://github.com/hebasto/bitcoin/pull/189.

ACKs for top commit:
  real-or-random:
    ACK f55703ba49

Tree-SHA512: 18190c062ae6e27d0ecbe7460cc22c960b25c0d35aa4b94f151d4b1c48f16e99fd5ecdfcb359784f95995292633d30d3d23b75a12be3aca5afffcc1e7e7daf31

CMakeLists.txt

@@ -263,6 +263,17 @@ endif()
 
 set(CMAKE_C_VISIBILITY_PRESET hidden)
 
+set(print_msan_notice)
+if(SECP256K1_BUILD_CTIME_TESTS)
+  include(CheckMemorySanitizer)
+  check_memory_sanitizer(msan_enabled)
+  if(msan_enabled)
+    try_append_c_flags(-fno-sanitize-memory-param-retval)
+    set(print_msan_notice YES)
+  endif()
+  unset(msan_enabled)
+endif()
+
 # Ask CTest to create a "check" target (e.g., make check) as alias for the "test" target.
 # CTEST_TEST_TARGET_ALIAS is not documented but supposed to be user-facing.
 # See: https://gitlab.kitware.com/cmake/cmake/-/commit/816c9d1aa1f2b42d40c81a991b68c96eb12b6d2
@@ -332,7 +343,7 @@ message("Valgrind .............................. ${SECP256K1_VALGRIND}")
 get_directory_property(definitions COMPILE_DEFINITIONS)
 string(REPLACE ";" " " definitions "${definitions}")
 message("Preprocessor defined macros ........... ${definitions}")
-message("C compiler ............................ ${CMAKE_C_COMPILER}")
+message("C compiler ............................ ${CMAKE_C_COMPILER_ID} ${CMAKE_C_COMPILER_VERSION}, ${CMAKE_C_COMPILER}")
 message("CFLAGS ................................ ${CMAKE_C_FLAGS}")
 get_directory_property(compile_options COMPILE_OPTIONS)
 string(REPLACE ";" " " compile_options "${compile_options}")
@@ -358,7 +369,14 @@ endif()
 if(SECP256K1_LATE_CFLAGS)
   message("SECP256K1_LATE_CFLAGS ................. ${SECP256K1_LATE_CFLAGS}")
 endif()
-message("\n")
+message("")
+if(print_msan_notice)
+  message(
+    "Note:\n"
+    "  MemorySanitizer detected, tried to add -fno-sanitize-memory-param-retval to compile options\n"
+    "  to avoid false positives in ctime_tests. Pass -DSECP256K1_BUILD_CTIME_TESTS=OFF to avoid this.\n"
+  )
+endif()
 if(SECP256K1_EXPERIMENTAL)
   message(
     "  ******\n"

build-aux/m4/bitcoin_secp.m4

@@ -50,10 +50,14 @@ AC_MSG_CHECKING(whether MemorySanitizer is enabled)
 AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
   #if defined(__has_feature)
   #  if __has_feature(memory_sanitizer)
-  #    error "MemorySanitizer is enabled."
+       /* MemorySanitizer is enabled. */
+  #  elif
+  #    error "MemorySanitizer is disabled."
   #  endif
+  #else
+  #  error "__has_feature is not defined."
   #endif
-  ]])], [msan_enabled=no], [msan_enabled=yes])
+  ]])], [msan_enabled=yes], [msan_enabled=no])
 AC_MSG_RESULT([$msan_enabled])
 ])
 

cmake/CheckMemorySanitizer.cmake

@@ -0,0 +1,18 @@
+include_guard(GLOBAL)
+include(CheckCSourceCompiles)
+
+function(check_memory_sanitizer output)
+  set(CMAKE_TRY_COMPILE_TARGET_TYPE STATIC_LIBRARY)
+  check_c_source_compiles("
+    #if defined(__has_feature)
+    #  if __has_feature(memory_sanitizer)
+         /* MemorySanitizer is enabled. */
+    #  elif
+    #    error \"MemorySanitizer is disabled.\"
+    #  endif
+    #else
+    #  error \"__has_feature is not defined.\"
+    #endif
+  " HAVE_MSAN)
+  set(${output} ${HAVE_MSAN} PARENT_SCOPE)
+endfunction()

configure.ac

@@ -248,7 +248,7 @@ if test x"$enable_ctime_tests" = x"auto"; then
 fi
 
 print_msan_notice=no
-if test x"$enable_ctime_tests" = x"yes" && test x"$GCC" = x"yes"; then
+if test x"$enable_ctime_tests" = x"yes"; then
   SECP_MSAN_CHECK
   # MSan on Clang >=16 reports unitialized memory in function parameters and return values, even if
   # the uninitalized variable is never actually "used". This is called "eager" checking, and it's