CDRIVER-2813 remove BSON_EXTRA_ALIGNMENT option

.evergreen/config_generator/components/loadbalanced.py

@@ -83,7 +83,6 @@ def tasks():
                 env={
                     'CC': _COMPILER,
                     'CFLAGS': '-fno-omit-frame-pointer',
-                    'EXTRA_CONFIGURE_FLAGS': '-DENABLE_EXTRA_ALIGNMENT=OFF',
                     'SSL': 'OPENSSL'
                 },
                 working_dir='mongoc',

.evergreen/config_generator/components/mock_server.py

@@ -42,7 +42,6 @@ def variants():
                 'CC': 'gcc',
                 'ASAN': 'on',
                 'CFLAGS': '-fno-omit-frame-pointer',
-                'EXTRA_CONFIGURE_FLAGS': '-DENABLE_EXTRA_ALIGNMENT=OFF',
                 'SANITIZE': 'address,undefined',
             }
         ),

.evergreen/config_generator/components/sanitizers/asan.py

@@ -10,7 +10,6 @@ def variants():
         'ASAN': 'on',
         'CFLAGS': '-fno-omit-frame-pointer',
         'CHECK_LOG': 'ON',
-        'EXTRA_CONFIGURE_FLAGS': '-DENABLE_EXTRA_ALIGNMENT=OFF',
         'SANITIZE': 'address,undefined',
     }
 

.evergreen/config_generator/components/sanitizers/tsan.py

@@ -9,7 +9,7 @@ def variants():
     expansions = {
         'CFLAGS': '-fno-omit-frame-pointer',
         'CHECK_LOG': 'ON',
-        'EXTRA_CONFIGURE_FLAGS': '-DENABLE_EXTRA_ALIGNMENT=OFF -DENABLE_SHM_COUNTERS=OFF',
+        'EXTRA_CONFIGURE_FLAGS': '-DENABLE_SHM_COUNTERS=OFF',
         'SANITIZE': 'thread',
     }
 

.evergreen/generated_configs/legacy-config.yml

@@ -368,7 +368,7 @@ tasks:
       shell: bash
       script: |-
         set -o errexit
-        env EXTRA_CONFIGURE_FLAGS="-DENABLE_EXTRA_ALIGNMENT=OFF" SNAPPY="OFF" ZLIB="BUNDLED" ZSTD="OFF" .evergreen/scripts/compile.sh
+        env SNAPPY="OFF" ZLIB="BUNDLED" ZSTD="OFF" .evergreen/scripts/compile.sh
   - func: upload-build
 - name: debug-compile-nosasl-nossl
   tags:
@@ -1311,7 +1311,7 @@ tasks:
       shell: bash
       script: |-
         set -o errexit
-        env SANITIZE=address SASL=AUTO SSL=OPENSSL EXTRA_CONFIGURE_FLAGS='-DENABLE_EXTRA_ALIGNMENT=OFF' .evergreen/scripts/compile.sh
+        env SANITIZE=address SASL=AUTO SSL=OPENSSL .evergreen/scripts/compile.sh
   - func: prepare-kerberos
   - func: run auth tests
     vars:

.evergreen/generated_configs/tasks.yml

@@ -2949,7 +2949,6 @@ tasks:
           env:
             CC: gcc
             CFLAGS: -fno-omit-frame-pointer
-            EXTRA_CONFIGURE_FLAGS: -DENABLE_EXTRA_ALIGNMENT=OFF
             SSL: OPENSSL
           args:
             - -c

.evergreen/generated_configs/variants.yml

@@ -180,7 +180,6 @@ buildvariants:
       ASAN: "on"
       CC: gcc
       CFLAGS: -fno-omit-frame-pointer
-      EXTRA_CONFIGURE_FLAGS: -DENABLE_EXTRA_ALIGNMENT=OFF
       SANITIZE: address,undefined
     tasks:
       - name: mock-server-test
@@ -194,7 +193,6 @@ buildvariants:
       ASAN: "on"
       CFLAGS: -fno-omit-frame-pointer
       CHECK_LOG: "ON"
-      EXTRA_CONFIGURE_FLAGS: -DENABLE_EXTRA_ALIGNMENT=OFF
       SANITIZE: address,undefined
     tasks:
       - name: .sanitizers-matrix-asan
@@ -203,7 +201,7 @@ buildvariants:
     expansions:
       CFLAGS: -fno-omit-frame-pointer
       CHECK_LOG: "ON"
-      EXTRA_CONFIGURE_FLAGS: -DENABLE_EXTRA_ALIGNMENT=OFF -DENABLE_SHM_COUNTERS=OFF
+      EXTRA_CONFIGURE_FLAGS: -DENABLE_SHM_COUNTERS=OFF
       SANITIZE: thread
     tasks:
       - name: .sanitizers-matrix-tsan

.evergreen/legacy_config_generator/evergreen_config_lib/tasks.py

@@ -151,7 +151,6 @@ class CompileWithClientSideEncryptionAsan(CompileTask):
         CFLAGS="-fno-omit-frame-pointer",
         COMPILE_LIBMONGOCRYPT="ON",
         CHECK_LOG="ON",
-        EXTRA_CONFIGURE_FLAGS="-DENABLE_EXTRA_ALIGNMENT=OFF",
         PATH="/usr/lib/llvm-3.8/bin:$PATH",
     )
     cls_tags: ClassVar[Sequence[str]] = ["client-side-encryption"]
@@ -191,7 +190,6 @@ def __init__(
         "debug-compile-no-align",
         tags=["debug-compile"],
         compression="zlib",
-        EXTRA_CONFIGURE_FLAGS="-DENABLE_EXTRA_ALIGNMENT=OFF",
     ),
     CompileTask("debug-compile-nosasl-nossl", tags=["debug-compile", "nosasl", "nossl"], SSL="OFF"),
     CompileTask("debug-compile-lto", CFLAGS="-flto"),
@@ -697,7 +695,7 @@ def pre_commands(self) -> Iterable[Value]:
                 func("find-cmake-latest"),
                 shell_mongoc(
                     """
-            env SANITIZE=address SASL=AUTO SSL=OPENSSL EXTRA_CONFIGURE_FLAGS='-DENABLE_EXTRA_ALIGNMENT=OFF' .evergreen/scripts/compile.sh
+            env SANITIZE=address SASL=AUTO SSL=OPENSSL .evergreen/scripts/compile.sh
             """,
                     add_expansions_to_env=True,
                 ),

CMakeLists.txt

@@ -185,19 +185,6 @@ mongo_bool_setting(
    ]]
 )
 
-# Deprecated options:
-mongo_bool_setting(
-   ENABLE_EXTRA_ALIGNMENT
-      "[Deprecated] Enable extra alignment on libbson types"
-   DEFAULT VALUE ON
-      DEVEL VALUE OFF
-   VALIDATE CODE [[
-      if(ENABLE_EXTRA_ALIGNMENT AND MONGO_SANITIZE MATCHES "undefined")
-         message(WARNING "ENABLE_EXTRA_ALIGNMENT=“${ENABLE_EXTRA_ALIGNMENT}” will create conflicts with UndefinedBehaviorSanitizer")
-      endif()
-   ]]
-)
-
 # Announce the build configuration. Used by `mlib_build_config_is()` in `mlib/config.h`
 add_compile_definitions(_MLIB_BUILD_CONFIG=$<CONFIG>)
 
@@ -302,8 +289,6 @@ if ( (ENABLE_BUILD_DEPENDECIES STREQUAL OFF) AND (NOT CMAKE_CURRENT_SOURCE_DIR S
    set (ENABLE_BUILD_DEPENDECIES ON)
 endif ()
 
-mongo_pick(BSON_EXTRA_ALIGN 1 0 ENABLE_EXTRA_ALIGNMENT)
-
 mongo_pick(MONGOC_ENABLE_RDTSCP 1 0 ENABLE_RDTSCP)
 
 mongo_pick(MONGOC_ENABLE_STATIC_BUILD 1 0 ENABLE_STATIC)

Earthfile

@@ -39,7 +39,6 @@ build:
     RUN cmake -S "$source_dir" -B "$build_dir" -G "Ninja Multi-Config" \
         -D ENABLE_MAINTAINER_FLAGS=ON \
         -D ENABLE_SHM_COUNTERS=ON \
-        -D ENABLE_EXTRA_ALIGNMENT=OFF \
         -D ENABLE_SASL=$(echo $sasl | __str upper) \
         -D ENABLE_SNAPPY=ON \
         -D ENABLE_SRV=ON \

src/libbson/NEWS

@@ -12,6 +12,10 @@ libbson 2.0.0 (Unreleased)
 * Compiling with `BSON_MEMCHECK` defined now has no effect.
 * Remove deprecated integral comparison interfaces: `bson_in_range_*` and `bson_cmp_*`.
 * Remove deprecated atomic and threading interfaces: `bson_atomic_*` and `bson_thrd_yield`.
+* The deprecated `ENABLE_EXTRA_ALIGNMENT` CMake option is removed.
+  * `bson_t` and `bson_iter_t` are now aligned to the size of a pointer.
+  * `BSON_ALIGNED_BEGIN` and `BSON_ALIGNED_END` now unconditionally apply their requested alignment.
+
 
 libbson 1.30.2
 ==============

src/libbson/doc/bson_t.rst

@@ -127,12 +127,11 @@ Synopsis
   #define BSON_APPEND_VALUE(b, key, val) \
      bson_append_value (b, key, (int) strlen (key), (val))
 
-  BSON_ALIGNED_BEGIN (128)
   typedef struct {
      uint32_t flags;       /* Internal flags for the bson_t. */
      uint32_t len;         /* Length of BSON data. */
      uint8_t padding[120]; /* Padding for stack allocation. */
-  } bson_t BSON_ALIGNED_END (128);
+  } bson_t;
 
 Description
 -----------

src/libbson/src/bson/bson-config.h.in

@@ -96,14 +96,6 @@
 #endif
 
 
-/*
- * Define to 1 if you want extra aligned types in libbson
- */
-#define BSON_EXTRA_ALIGN @BSON_EXTRA_ALIGN@
-#if BSON_EXTRA_ALIGN != 1
-# undef BSON_EXTRA_ALIGN
-#endif
-
 
 /*
  * Define to 1 if you have rand_r available on your platform.

src/libbson/src/bson/bson-macros.h

@@ -162,23 +162,13 @@
 #define BSON_ALIGN_OF_PTR (BSON_ALIGNOF (void *))
 #endif
 
-#ifdef BSON_EXTRA_ALIGN
-#if defined(_MSC_VER)
-#define BSON_ALIGNED_BEGIN(_N) __declspec (align (_N))
-#define BSON_ALIGNED_END(_N)
-#else
-#define BSON_ALIGNED_BEGIN(_N)
-#define BSON_ALIGNED_END(_N) __attribute__ ((aligned (_N)))
-#endif
-#else
 #if defined(_MSC_VER)
 #define BSON_ALIGNED_BEGIN(_N) __declspec (align (BSON_ALIGN_OF_PTR))
 #define BSON_ALIGNED_END(_N)
 #else
 #define BSON_ALIGNED_BEGIN(_N)
 #define BSON_ALIGNED_END(_N) __attribute__ ((aligned ((_N) > BSON_ALIGN_OF_PTR ? BSON_ALIGN_OF_PTR : (_N))))
 #endif
-#endif
 
 
 #define bson_str_empty(s) (!s[0])

src/libbson/src/bson/bson-private.h

@@ -43,18 +43,18 @@ typedef enum {
 #define BSON_INLINE_DATA_SIZE 120
 
 
-BSON_ALIGNED_BEGIN (128)
+BSON_ALIGNED_BEGIN (BSON_ALIGN_OF_PTR)
 typedef struct {
    bson_flags_t flags;
    uint32_t len;
    uint8_t data[BSON_INLINE_DATA_SIZE];
-} bson_impl_inline_t BSON_ALIGNED_END (128);
+} bson_impl_inline_t BSON_ALIGNED_END (BSON_ALIGN_OF_PTR);
 
 
 BSON_STATIC_ASSERT2 (impl_inline_t, sizeof (bson_impl_inline_t) == 128);
 
 
-BSON_ALIGNED_BEGIN (128)
+BSON_ALIGNED_BEGIN (BSON_ALIGN_OF_PTR)
 typedef struct {
    bson_flags_t flags; /* flags describing the bson_t */
    /* len is part of the public bson_t declaration. It is not
@@ -71,7 +71,7 @@ typedef struct {
    size_t alloclen;           /* length of buffer that we own. */
    bson_realloc_func realloc; /* our realloc implementation */
    void *realloc_func_ctx;    /* context for our realloc func */
-} bson_impl_alloc_t BSON_ALIGNED_END (128);
+} bson_impl_alloc_t BSON_ALIGNED_END (BSON_ALIGN_OF_PTR);
 
 
 BSON_STATIC_ASSERT2 (impl_alloc_t, sizeof (bson_impl_alloc_t) <= 128);

src/libbson/src/bson/bson-types.h

@@ -120,11 +120,11 @@ typedef struct _bson_json_opts_t bson_json_opts_t;
  *
  * This structure is meant to fit in two sequential 64-byte cachelines.
  */
-BSON_ALIGNED_BEGIN (128) typedef struct _bson_t {
+BSON_ALIGNED_BEGIN (BSON_ALIGN_OF_PTR) typedef struct _bson_t {
    uint32_t flags;       /* Internal flags for the bson_t. */
    uint32_t len;         /* Length of BSON data. */
    uint8_t padding[120]; /* Padding for stack allocation. */
-} bson_t BSON_ALIGNED_END (128);
+} bson_t BSON_ALIGNED_END (BSON_ALIGN_OF_PTR);
 
 /**
  * BSON_INITIALIZER:
@@ -342,7 +342,7 @@ typedef struct _bson_value_t {
  * This structure is safe to discard on the stack. No cleanup is necessary
  * after using it.
  */
-BSON_ALIGNED_BEGIN (128)
+BSON_ALIGNED_BEGIN (BSON_ALIGN_OF_PTR)
 typedef struct {
    const uint8_t *raw; /* The raw buffer being iterated. */
    uint32_t len;       /* The length of raw. */
@@ -356,7 +356,7 @@ typedef struct {
    uint32_t next_off;  /* The offset of the next field. */
    uint32_t err_off;   /* The offset of the error. */
    bson_value_t value; /* Internal value for various state. */
-} bson_iter_t BSON_ALIGNED_END (128);
+} bson_iter_t BSON_ALIGNED_END (BSON_ALIGN_OF_PTR);
 
 
 /**