ext/wasm/mkwasmbuilds.c - chromium/deps/sqlite - Git at Google

 /*
 ** 2024-09-23
 **
 ** The author disclaims copyright to this source code.  In place of
 ** a legal notice, here is a blessing:
 **
 **    May you do good and not evil.
 **    May you find forgiveness for yourself and forgive others.
 **    May you share freely, never taking more than you give.
 **
 *************************************************************************
 **
 ** This app's single purpose is to emit parts of the Makefile code for
 ** sqlite3's canonical WASM build. The main motivation is to generate
 ** code which "could" be created via GNU Make's eval command but is
 ** highly illegible when constructed that way. Attempts to write this
 ** app in Bash and TCL have suffered from the problem that those
 ** languages require escaping $ symbols, making the resulting script
 ** code as illegible as the eval spaghetti we want to get away
 ** from. Maintaining it in C is, somewhat surprisingly, _slightly_
 ** less illegible than writing it in bash, tcl, or native Make code.
 **
 ** The emitted makefile code is not standalone - it depends on
 ** variables and $(call)able functions from the main makefile.
 */

 #undef NDEBUG
 #define DEBUG 1
 #include <assert.h>
 #include <stdio.h>
 #include <string.h>

 #define pf printf
 #define ps puts

 /*
 ** Valid build names. Each build is a combination of one of these and
 ** one of JS_BUILD_MODES, but only certain combinations are legal.
 ** This macro and JS_BUILD_MODES exist solely for documentation
 ** purposes: they are not expanded into code anywhere.
 */
 #define JS_BUILD_NAMES sqlite3 sqlite3-wasmfs
 /*
 ** Valid build modes. For the "sqlite3-wasmfs" build, only "esm" (ES6
 ** Module) is legal.
 */
 #define JS_BUILD_MODES vanilla esm bundler-friendly node

 /* Separator to help eyeballs find the different output sections */
 static const char * zBanner =
   "\n########################################################################\n";

 /*
 ** Flags for use with BuildDef::flags and the 3rd argument to
 ** mk_pre_post().
 **
 ** Maintenance reminder: do not combine flags within this enum,
 ** e.g. LIBMODE_BUNDLER_FRIENDLY=0x02|LIBMODE_ESM, as that will lead
 ** to breakage in some of the flag checks.
 */
 enum LibModeFlags {
   /* The canonical build */
   LIBMODE_MAIN = 0x01,
   /* Indicates an ESM module build. */
   LIBMODE_ESM = 0x02,
   /* Indicates a "bundler-friendly" build mode. */
   LIBMODE_BUNDLER_FRIENDLY = 0x04,
   /* Indicates that this is an unsupported build mode. These builds
      are not added to the 'all' target. */
   LIBMODE_UNSUPPORTED = 0x08,
   /* Indicates a node.js-for-node.js build (untested and
   ** unsupported). */
   LIBMODE_NODEJS = 0x10,
   /* Indicates a wasmfs build (untested and unsupported). */
   LIBMODE_WASMFS = 0x20,
   /* Indicates that this build creates a file named "sqlite3.wasm" as
      a side-effect of creating the .js/.mjs file. */
   LIBMODE_SQLITE3_WASM = 0x40,
   /* Indicates that the generated .js/.mjs file needs to be patched to
      rename its reference to "sqlite3-XYZ.wasm" to "sqlite3.wasm". */
   LIBMODE_PATCH_WASM_NAME = 0x80
 };

 /*
 ** Info needed for building one combination of JS_BUILD_NAMES and
 ** JS_BUILD_MODE, noting that only a subset of those combinations are
 ** legal/sensical.
 */
 struct BuildDef {
   const char *zName;      /* Name from JS_BUILD_NAMES */
   const char *zMode;      /* Name from JS_BUILD_MODES */
   int flags;              /* Flags from LibModeFlags */
   const char *zJsOut;     /* Base name of generated sqlite3.js/.mjs */
   /* TODO? dynamically determine zJsOut based on zName, zMode, and
   ** flags. */
   const char *zCmppD;     /* Extra -D... flags for c-pp */
   const char *zEmcc;      /* Extra flags for emcc */
 };
 typedef struct BuildDef BuildDef;

 /*
 ** The set of WASM builds for the library (as opposed to the apps
 ** (fiddle, speedtest1)). This array must end with an empty sentinel
 ** entry. Their order is mostly insignificant, but some makefile vars
 ** used by some builds are set up by prior builds. Because of that,
 ** the (sqlite3, vanilla), (sqlite3, esm), and (sqlite3,
 ** bundler-friendly) builds should be defined first (in that order).
 */
 const BuildDef aBuildDefs[] = {
   {/* Core build */
     "sqlite3", "vanilla", LIBMODE_MAIN | LIBMODE_SQLITE3_WASM,
     "sqlite3.js", 0, 0},

   {/* Core ESM */
    "sqlite3", "esm", LIBMODE_ESM | LIBMODE_SQLITE3_WASM,
    "sqlite3.mjs",  "-Dtarget=es6-module", 0},

   {/* Core bundler-friend. Untested and "not really" supported, but
    ** required by the downstream npm subproject. */
     "sqlite3", "bundler-friendly",
     LIBMODE_BUNDLER_FRIENDLY | LIBMODE_PATCH_WASM_NAME | LIBMODE_ESM,
     "sqlite3-bundler-friendly.mjs",
     "$(c-pp.D.sqlite3-esm) -Dtarget=es6-bundler-friendly", 0},

   {/* node.js mode. Untested and unsupported. */
     "sqlite3", "node", LIBMODE_NODEJS | LIBMODE_UNSUPPORTED,
     "sqlite3-node.mjs",
     "$(c-pp.D.sqlite3-bundler-friendly) -Dtarget=node", 0},

   {/* The wasmfs build is optional, untested, unsupported, and
    ** needs to be invoked conditionally using info we don't have
    ** here. */
     "sqlite3-wasmfs", "esm" ,
     LIBMODE_WASMFS | LIBMODE_ESM | LIBMODE_UNSUPPORTED,
     "sqlite3-wasmfs.mjs",
     "$(c-pp.D.sqlite3-bundler-friendly) -Dwasmfs",
     "-sEXPORT_ES6 -sUSE_ES6_IMPORT_META"},

   {/*End-of-list sentinel*/0,0,0,0,0,0}
 };

 /*
 ** Emits common vars needed by the rest of the emitted code (but not
 ** needed by makefile code outside of these generated pieces).
 */
 static void mk_prologue(void){
   /* A 0-terminated list of makefile vars which we expect to have been
   ** set up by this point in the build process. There are some which
   ** we can't check here because they are not defined until after
   ** these rules are included, but this set covers the basics. */
   char const * aRequiredVars[] = {
     "dir.top",
     "dir.api", "dir.dout", "dir.tmp",
     "sqlite3-license-version.js",
     "MAKEFILE", "MAKEFILE_LIST",
     /* Fiddle... */
     "dir.fiddle", "dir.fiddle-debug",
     "MAKEFILE.fiddle",
     "EXPORTED_FUNCTIONS.fiddle",
     /*"just-testing",*/
     0
   };
   char const * zVar;
   int i;
   pf("%s# Build setup sanity checks...\n", zBanner);
   for( i = 0; (zVar = aRequiredVars[i]); ++i ){
     pf("ifeq (,$(%s))\n", zVar);
     pf("  $(error build process error: expecting make var $$(%s) to "
        "have been set up by now)\n", zVar);
     ps("endif");
   }
   pf("%s", zBanner);
   ps("# extern-post-js* and extern-pre-js* are files for use with");
   ps("# Emscripten's --extern-pre-js and --extern-post-js flags.");
   ps("extern-pre-js.js = $(dir.api)/extern-pre-js.js");
   ps("extern-post-js.js.in = $(dir.api)/extern-post-js.c-pp.js");
   ps("# Emscripten flags for --[extern-][pre|post]-js=... for the");
   ps("# various builds.");
   ps("pre-post-common.flags = --extern-pre-js=$(sqlite3-license-version.js)");
   ps("# pre-post-jses.deps.* = a list of dependencies for the\n"
      "# --[extern-][pre/post]-js files.");
   ps("pre-post-jses.deps.common = $(extern-pre-js.js) $(sqlite3-license-version.js)");

   {
     /* SQLITE.CALL.WASM-OPT = shell code to run $(1) (source wasm file
     ** name) through $(bin.wasm-opt) */
     const char * zOptFlags =
       /*
       ** Flags for wasm-opt. It has many, many, MANY "passes" options
       ** and the ones which appear here were selected solely on the
       ** basis of trial and error.
       **
       ** All wasm file size savings/costs mentioned below are based on
       ** the vanilla build of sqlite3.wasm with -Oz (our shipping
       ** configuration). Comments like "saves nothing" may not be
       ** technically correct: "nothing" means "some neglible amount."
       **
       ** Note that performance gains/losses are _not_ taken into
       ** account here: only wasm file size.
       */
       "--enable-bulk-memory-opt " /* required */
       "--all-features "           /* required */
       "--post-emscripten "        /* Saves roughly 12kb */
       "--strip-debug "            /* We already wasm-strip, but in
                                   ** case this environment has no
                                   ** wasm-strip... */
       /*
       ** The rest are trial-and-error. See wasm-opt --help and search
       ** for "Optimization passes" to find the full list.
       **
       ** With many flags this gets unusuably slow.
       */
       /*"--converge " saves nothing for the options we're using */
       /*"--dce " saves nothing */
       /*"--directize " saves nothing */
       /*"--gsi " no: requires --closed-world flag, which does not
       ** sound like something we want. */
       /*"--gufa --gufa-cast-all --gufa-optimizing " costs roughly 2kb */
       /*"--heap-store-optimization " saves nothing */
       /*"--heap2local " saves nothing */
       //"--inlining --inlining-optimizing " costs roughly 3kb */
       "--local-cse " /* saves roughly 1kb */
       /*"--once-reduction " saves nothing */
       /*"--remove-memory-init " presumably a performance tweak */
       /*"--remove-unused-names " saves nothing */
       /*"--safe-heap "*/
       /*"--vacuum " saves nothing */
       ;
     ps("ifeq (,$(bin.wasm-opt))");
     ps("define SQLITE.CALL.WASM-OPT");
     ps("echo 'wasm-opt not available for $(1)'");
     ps("endef");
     ps("else");
     ps("define SQLITE.CALL.WASM-OPT");
     pf("echo -n 'Before wasm-opt:'; ls -l $(1);\\\n"
        "\trm -f wasm-opt-tmp.wasm;\\\n"
        /* It's very likely that the set of wasm-opt flags varies from
        ** version to version, so we'll ignore any errors here. */
        "\tif $(bin.wasm-opt) $(1) -o wasm-opt-tmp.wasm \\\n"
        "\t\t%s; then \\\n"
        "\t\tmv wasm-opt-tmp.wasm $(1); \\\n"
        "\t\techo -n 'After wasm-opt: '; \\\n"
        "\t\tls -l $(1); \\\n"
        "\telse \\\n"
        "\t\techo 'WARNING: ignoring wasm-opt failure for $(1)'; \\\n"
        "\tfi\n",
        zOptFlags
     );
     ps("endef");
     ps("endif");
   }
 }

 /*
 ** Emits makefile code for setting up values for the --pre-js=FILE,
 ** --post-js=FILE, and --extern-post-js=FILE emcc flags, as well as
 ** populating those files.
 */
 static void mk_pre_post(const char *zName  /* build name */,
                         const char *zMode  /* build mode */,
                         const char *zCmppD /* optional -D flags for c-pp for the
                                            ** --pre/--post-js files. */){
 /* Very common printf() args combo. */
 #define zNM zName, zMode

   pf("%s# Begin --pre/--post flags for %s-%s\n", zBanner, zNM);
   pf("c-pp.D.%s-%s = %s\n", zNM, zCmppD ? zCmppD : "");
   pf("pre-post-%s-%s.flags ?=\n", zNM);

   /* --pre-js=... */
   pf("pre-js.js.%s-%s = $(dir.tmp)/pre-js.%s-%s.js\n",
      zNM, zNM);
   pf("$(pre-js.js.%s-%s): $(MAKEFILE_LIST) $(sqlite3-license-version.js)\n", zNM);
 #if 1
   pf("$(eval $(call SQLITE.CALL.C-PP.FILTER,$(pre-js.js.in),$(pre-js.js.%s-%s),"
      "$(c-pp.D.%s-%s)))\n", zNM, zNM);
 #else
   /* This part is needed if/when we re-enable the custom
   ** Module.instantiateModule() impl in api/pre-js.c-pp.js. */
   pf("pre-js.js.%s-%s.intermediary = $(dir.tmp)/pre-js.%s-%s.intermediary.js\n",
      zNM, zNM);
   pf("$(eval $(call SQLITE.CALL.C-PP.FILTER,$(pre-js.js.in),$(pre-js.js.%s-%s.intermediary),"
      "$(c-pp.D.%s-%s) -Dcustom-Module.instantiateModule))\n", zNM, zNM);
   pf("$(pre-js.js.%s-%s): $(pre-js.js.%s-%s.intermediary)\n", zNM, zNM);
   pf("\tcp $(pre-js.js.%s-%s.intermediary) $@\n", zNM);

   /* Amend $(pre-js.js.zName-zMode) for all targets except the plain
   ** "sqlite3" and the "sqlite3-wasmfs" builds... */
   if( 0!=strcmp("sqlite3-wasmfs", zName)
       && 0!=strcmp("sqlite3", zName) ){
 #error "This part ^^^ is needs adapting for use with the LIBMODE_... flags"
     pf("\t@echo 'Module[xNameOfInstantiateWasm].uri = "
        "\"%s.wasm\";' >> $@\n", zName);
   }
 #endif

   /* --post-js=... */
   pf("post-js.js.%s-%s = $(dir.tmp)/post-js.%s-%s.js\n", zNM, zNM);
   pf("$(eval $(call SQLITE.CALL.C-PP.FILTER,$(post-js.js.in),"
      "$(post-js.js.%s-%s),$(c-pp.D.%s-%s)))\n", zNM, zNM);

   /* --extern-post-js=... */
   pf("extern-post-js.js.%s-%s = $(dir.tmp)/extern-post-js.%s-%s.js\n", zNM, zNM);
   pf("$(eval $(call SQLITE.CALL.C-PP.FILTER,$(extern-post-js.js.in),$(extern-post-js.js.%s-%s),"
      "$(c-pp.D.%s-%s)))\n", zNM, zNM);

   /* Combined flags for use with emcc... */
   pf("pre-post-common.flags.%s-%s = "
      "$(pre-post-common.flags) "
      "--post-js=$(post-js.js.%s-%s) "
      "--extern-post-js=$(extern-post-js.js.%s-%s)\n", zNM, zNM, zNM);

   pf("pre-post-%s-%s.flags += $(pre-post-common.flags.%s-%s) "
      "--pre-js=$(pre-js.js.%s-%s)\n", zNM, zNM, zNM);

   /* Set up deps... */
   pf("pre-post-jses.%s-%s.deps = $(pre-post-jses.deps.common) "
      "$(post-js.js.%s-%s) $(extern-post-js.js.%s-%s)\n",
      zNM, zNM, zNM);
   pf("pre-post-%s-%s.deps = $(pre-post-jses.%s-%s.deps) $(dir.tmp)/pre-js.%s-%s.js\n",
      zNM, zNM, zNM);
   pf("# End --pre/--post flags for %s-%s%s", zNM, zBanner);
 #undef zNM
 }

 /*
 ** Emits rules for the fiddle builds.
 */
 static void mk_fiddle(void){
   int i = 0;

   mk_pre_post("fiddle-module","vanilla", 0);
   for( ; i < 2; ++i ){
     /* 0==normal, 1==debug */
     const char *zTail = i ? ".debug" : "";
     const char *zDir = i ? "$(dir.fiddle-debug)" : "$(dir.fiddle)";

     pf("%s# Begin fiddle%s\n", zBanner, zTail);
     pf("fiddle-module.js%s = %s/fiddle-module.js\n", zTail, zDir);
     pf("fiddle-module.wasm%s = "
        "$(subst .js,.wasm,$(fiddle-module.js%s))\n", zTail, zTail);
     pf("$(fiddle-module.js%s):%s $(MAKEFILE_LIST) $(MAKEFILE.fiddle) "
        "$(EXPORTED_FUNCTIONS.fiddle) "
        "$(fiddle.cses) $(pre-post-fiddle-module-vanilla.deps) "
        "$(SOAP.js)\n",
        zTail, (i ? " $(fiddle-module.js)" : ""));
     if( 1==i ){/*fiddle.debug*/
       pf("\t@test -d \"$(dir $@)\" || mkdir -p \"$(dir $@)\"\n");
     }
     pf("\t$(bin.emcc) -o $@ $(fiddle.emcc-flags%s) "
        "$(pre-post-fiddle-module-vanilla.flags) $(fiddle.cses)\n",
        zTail);
     pf("\t$(maybe-wasm-strip) $(fiddle-module.wasm%s)\n", zTail);
     pf("\t@cp -p $(SOAP.js) $(dir $@)\n");
     if( 1==i ){/*fiddle.debug*/
       pf("\tcp -p $(dir.fiddle)/index.html "
          "$(dir.fiddle)/fiddle.js "
          "$(dir.fiddle)/fiddle-worker.js "
          "$(dir $@)\n");
     }
     pf("\t@for i in %s/*.*js %s/*.html %s/*.wasm; do \\\n"
        "\t\ttest -f $${i} || continue;             \\\n"
        "\t\tgzip < $${i} > $${i}.gz; \\\n"
        "\tdone\n", zDir, zDir, zDir);
     if( 0==i ){
       ps("fiddle: $(fiddle-module.js)");
     }else{
       ps("fiddle-debug: $(fiddle-module-debug.js)");
     }
     pf("# End fiddle%s%s", zTail, zBanner);
   }
 }

 /*
 ** Emits makefile code for one build of the library, primarily defined
 ** by the combination of zName and zMode, each of which must be values
 ** from JS_BUILD_NAMES resp. JS_BUILD_MODES.
 */
 static void mk_lib_mode(const BuildDef * pB){
   char aOutBuf[1024] = {0};
   const char * zWasmOut = "$(basename $@).wasm"
     /* The various targets named X.js or X.mjs (zJsOut) also generate
     ** X.wasm, and we need that part of the name to perform some
     ** post-processing after Emscripten generates X.wasm. */;
   assert( pB->zName );
   assert( pB->zMode );
   assert( pB->zJsOut );
 /* Very common printf() args combo. */
 #define zNM pB->zName, pB->zMode

   pf("%s# Begin build [%s-%s]. flags=0x%02x\n", zBanner, zNM, pB->flags);
   pf("# zJsOut=%s\n# zCmppD=%s\n", pB->zJsOut,
      pB->zCmppD ? pB->zCmppD : "<none>");
   pf("$(info Setting up build [%s-%s]: %s)\n", zNM, pB->zJsOut);
   mk_pre_post(zNM, pB->zCmppD);

   snprintf(aOutBuf, sizeof(aOutBuf), "$(dir.tmp)/%s-%s", zNM);

   /* Set up build-specific output dir. Several of the builds generate
   ** a file named sqlite3.wasm, which precludes us building them in
   ** parallel. We use a build-specific dir to enable parallization of
   ** those builds. All such builds will generate a byte-for-byte
   ** identical sqlite3.wasm so long as all Emscripten-related flags
   ** which influence that file are the same (i.e. where pB->zEmcc is
   ** the same), which is the case for most of the affected builds. */
   pf("dir.tmp.%s-%s = %s\n", zNM, aOutBuf);
   pf("$(dir.tmp.%s-%s):\n\tmkdir -p $@\n", zNM);
 #if 0
   /* We don't need to add cleanup rules so long as these dirs are
   ** under $(dir.tmp), as that dir will be cleaned up by 'make
   ** clean'. If these dirs move somewhere else, we'll want to add a
   ** rule like...*/
   pf("clean-%s-%s:\n\trm -fr $(dir.tmp.%s-%s)\n"
     "clean: clean-%s-%s\n", zNM, zNM, zNM);
 #endif

   pf("\nemcc.flags.%s.%s ?=\n", zNM);
   if( pB->zEmcc && pB->zEmcc[0] ){
     pf("emcc.flags.%s.%s += %s\n", zNM, pB->zEmcc);
   }

   /* target pB->zJsOut */
   pf("$(dir.tmp.%s-%s)/%s: "
      "$(dir.tmp.%s-%s) "
      "$(MAKEFILE_LIST) $(sqlite3-wasm.cfiles) $(EXPORTED_FUNCTIONS.api) "
      "$(pre-post-%s-%s.deps) "
      "$(sqlite3-api.ext.jses)"
      /* ^^^ maintenance reminder: we set these as deps so that they
      ** get copied into place early. That allows the developer to
      ** reload the base-most test pages while the later-stage builds
      ** are still compiling, which is especially helpful when running
      ** builds with long build times (like -Oz). */
      "\n",
      zNM, pB->zJsOut, zNM, zNM);
   pf("\t@echo \"Building [%s-%s] %s ...\"\n", zNM, pB->zJsOut);
   pf("\t$(bin.emcc) -o $@ $(emcc_opt_full) $(emcc.flags) \\\n");
   pf("\t\t$(emcc.jsflags) -sENVIRONMENT=$(emcc.environment.%s) \\\n",
      pB->zMode);
   pf("\t\t$(pre-post-%s-%s.flags) \\\n", zNM);
   pf("\t\t$(emcc.flags.%s) $(emcc.flags.%s.%s) \\\n", pB->zName, zNM);
   pf("\t\t$(cflags.common) $(SQLITE_OPT) \\\n"
      "\t\t$(cflags.%s) $(cflags.%s.%s) \\\n"
      "\t\t$(cflags.wasm_extra_init) $(sqlite3-wasm.cfiles)\n", pB->zName, zNM);
   if( (LIBMODE_ESM & pB->flags) || (LIBMODE_NODEJS & pB->flags) ){
     /* TODO? Replace this $(call) with the corresponding makefile
     ** code.  OTOH, we also use this $(call) in the speedtest1-wasmfs
     ** build, which is not part of the rules emitted by this
     ** program. */
     pf("\t@$(call SQLITE.CALL.xJS.ESM-EXPORT-DEFAULT,1,%d)\n",
        (LIBMODE_WASMFS & pB->flags) ? 1 : 0);
   }
   pf("\t@chmod -x %s; \\\n"
      "\t\t$(maybe-wasm-strip) %s;\n",
      zWasmOut, zWasmOut)
     /* For whatever reasons, .wasm files get built with their +x bit
     ** set. That upsets althttpd, which uses +x as an indication that
     ** the file is a CGI script. There's no apparent useful reason to
     ** have +x set on these, so we -x them. */;
   pf("\t@$(call SQLITE.CALL.WASM-OPT,%s)\n", zWasmOut);
   pf(/* Our JS code installs bindings of each WASM export. The
      ** generated Emscripten JS file does the same using its own
      ** framework, but we don't use those results and can speed up lib
      ** init, and reduce memory cost a bit, by stripping them out. Of
      ** of this writing, this strips approximately 25kb of JS code. */
     "\t@sed -i -e '/^.*= *_sqlite.*= *createExportWrapper/d' $@ || exit; \\\n"
     /*  ^^^^^^ reminder: Mac/BSD sed has no -i flag */
     "\t\techo 'Stripped out createExportWrapper() parts.'\n");
   /*
   ** The above $(bin.emcc) call will write pB->zJsOut and will create
   ** a like-named .wasm file (zWasmOut). That .wasm file name gets
   ** hard-coded into zJsOut so we need to, for some cases, patch
   ** zJsOut to use the name sqlite3.wasm instead. Note that the
   ** resulting .wasm file is identical for all builds for which
   ** pB->zEmcc is empty.
   */
   if( (LIBMODE_PATCH_WASM_NAME & pB->flags) ){
     pf("\t@echo 'Patching $@ for %s.wasm...'; \\\n", pB->zName);
     pf("\t\trm -f %s; \\\n", zWasmOut);
     pf("\t\tsed -i -e 's/%s-%s.wasm/%s.wasm/g' $@ || exit;\n",
        /* ^^^^^^ reminder: Mac/BSD sed has no -i flag but this
        ** build process explicitly requires a Linux system. */
        zNM, pB->zName);
     pf("\t@ls -la $@\n");
     if( LIBMODE_BUNDLER_FRIENDLY & pB->flags ){
       /* Avoid a 3rd occurrence of the bug fixed by 65798c09a00662a3,
       ** which was (in two cases) caused by makefile refactoring and
       ** not recognized until after a release was made with the broken
       ** sqlite3-bundler-friendly.mjs (which is used by the npm
       ** subproject but is otherwise untested/unsupported): */
       pf("\t@if grep -e '^ *importScripts(' $@; "
          "then echo 'ERROR: bug fixed in 65798c09a00662a3 has re-appeared'; "
          "exit 1; fi;\n");
     }
   }else{
     pf("\t@ls -la %s $@\n", zWasmOut);
   }
   pf("\n$(dir.dout)/%s: $(dir.tmp.%s-%s)/%s\n", pB->zJsOut, zNM, pB->zJsOut);
   pf("\t@cp -p $(dir.tmp.%s-%s)/%s $(dir.dout)/.\n", zNM, pB->zJsOut);
   if( (LIBMODE_SQLITE3_WASM & pB->flags) ){
     pf("\t@cp -p $(dir.tmp.%s-%s)/*.wasm $(dir.dout)/.\n", zNM);
   }
   if( 0==(LIBMODE_UNSUPPORTED & pB->flags) ){
     pf("all: $(dir.dout)/%s\n", pB->zJsOut);
   }
   pf("%s-%s: $(dir.tmp.%s-%s)/%s\n", zNM, zNM, pB->zJsOut);
   pf("# End build [%s-%s]%s", zNM, zBanner);
 #undef zNM
 }

 int main(void){
   int rc = 0;
   const BuildDef *pB = &aBuildDefs[0];
   pf("# What follows was GENERATED by %s. Edit at your own risk.\n", __FILE__);
   mk_prologue();
   for( ; pB->zName; ++pB ){
     mk_lib_mode( pB );
   }
   mk_fiddle();
   mk_pre_post("speedtest1","vanilla", 0);
   mk_pre_post("speedtest1-wasmfs","esm",
               "$(c-pp.D.sqlite3-bundler-friendly) -Dwasmfs");
   return rc;
 }
	/*
	** 2024-09-23
	**
	** The author disclaims copyright to this source code. In place of
	** a legal notice, here is a blessing:
	**
	** May you do good and not evil.
	** May you find forgiveness for yourself and forgive others.
	** May you share freely, never taking more than you give.
	**
	*************************************************************************
	**
	** This app's single purpose is to emit parts of the Makefile code for
	** sqlite3's canonical WASM build. The main motivation is to generate
	** code which "could" be created via GNU Make's eval command but is
	** highly illegible when constructed that way. Attempts to write this
	** app in Bash and TCL have suffered from the problem that those
	** languages require escaping $ symbols, making the resulting script
	** code as illegible as the eval spaghetti we want to get away
	** from. Maintaining it in C is, somewhat surprisingly, _slightly_
	** less illegible than writing it in bash, tcl, or native Make code.
	**
	** The emitted makefile code is not standalone - it depends on
	** variables and $(call)able functions from the main makefile.
	*/

	#undef NDEBUG
	#define DEBUG 1
	#include <assert.h>
	#include <stdio.h>
	#include <string.h>

	#define pf printf
	#define ps puts

	/*
	** Valid build names. Each build is a combination of one of these and
	** one of JS_BUILD_MODES, but only certain combinations are legal.
	** This macro and JS_BUILD_MODES exist solely for documentation
	** purposes: they are not expanded into code anywhere.
	*/
	#define JS_BUILD_NAMES sqlite3 sqlite3-wasmfs
	/*
	** Valid build modes. For the "sqlite3-wasmfs" build, only "esm" (ES6
	** Module) is legal.
	*/
	#define JS_BUILD_MODES vanilla esm bundler-friendly node

	/* Separator to help eyeballs find the different output sections */
	static const char * zBanner =
	"\n########################################################################\n";

	/*
	** Flags for use with BuildDef::flags and the 3rd argument to
	** mk_pre_post().
	**
	** Maintenance reminder: do not combine flags within this enum,
	** e.g. LIBMODE_BUNDLER_FRIENDLY=0x02\|LIBMODE_ESM, as that will lead
	** to breakage in some of the flag checks.
	*/
	enum LibModeFlags {
	/* The canonical build */
	LIBMODE_MAIN = 0x01,
	/* Indicates an ESM module build. */
	LIBMODE_ESM = 0x02,
	/* Indicates a "bundler-friendly" build mode. */
	LIBMODE_BUNDLER_FRIENDLY = 0x04,
	/* Indicates that this is an unsupported build mode. These builds
	are not added to the 'all' target. */
	LIBMODE_UNSUPPORTED = 0x08,
	/* Indicates a node.js-for-node.js build (untested and
	** unsupported). */
	LIBMODE_NODEJS = 0x10,
	/* Indicates a wasmfs build (untested and unsupported). */
	LIBMODE_WASMFS = 0x20,
	/* Indicates that this build creates a file named "sqlite3.wasm" as
	a side-effect of creating the .js/.mjs file. */
	LIBMODE_SQLITE3_WASM = 0x40,
	/* Indicates that the generated .js/.mjs file needs to be patched to
	rename its reference to "sqlite3-XYZ.wasm" to "sqlite3.wasm". */
	LIBMODE_PATCH_WASM_NAME = 0x80
	};

	/*
	** Info needed for building one combination of JS_BUILD_NAMES and
	** JS_BUILD_MODE, noting that only a subset of those combinations are
	** legal/sensical.
	*/
	struct BuildDef {
	const char zName; / Name from JS_BUILD_NAMES */
	const char zMode; / Name from JS_BUILD_MODES */
	int flags; /* Flags from LibModeFlags */
	const char zJsOut; / Base name of generated sqlite3.js/.mjs */
	/* TODO? dynamically determine zJsOut based on zName, zMode, and
	** flags. */
	const char zCmppD; / Extra -D... flags for c-pp */
	const char zEmcc; / Extra flags for emcc */
	};
	typedef struct BuildDef BuildDef;

	/*
	** The set of WASM builds for the library (as opposed to the apps
	** (fiddle, speedtest1)). This array must end with an empty sentinel
	** entry. Their order is mostly insignificant, but some makefile vars
	** used by some builds are set up by prior builds. Because of that,
	** the (sqlite3, vanilla), (sqlite3, esm), and (sqlite3,
	** bundler-friendly) builds should be defined first (in that order).
	*/
	const BuildDef aBuildDefs[] = {
	{/* Core build */
	"sqlite3", "vanilla", LIBMODE_MAIN \| LIBMODE_SQLITE3_WASM,
	"sqlite3.js", 0, 0},

	{/* Core ESM */
	"sqlite3", "esm", LIBMODE_ESM \| LIBMODE_SQLITE3_WASM,
	"sqlite3.mjs", "-Dtarget=es6-module", 0},

	{/* Core bundler-friend. Untested and "not really" supported, but
	** required by the downstream npm subproject. */
	"sqlite3", "bundler-friendly",
	LIBMODE_BUNDLER_FRIENDLY \| LIBMODE_PATCH_WASM_NAME \| LIBMODE_ESM,
	"sqlite3-bundler-friendly.mjs",
	"$(c-pp.D.sqlite3-esm) -Dtarget=es6-bundler-friendly", 0},

	{/* node.js mode. Untested and unsupported. */
	"sqlite3", "node", LIBMODE_NODEJS \| LIBMODE_UNSUPPORTED,
	"sqlite3-node.mjs",
	"$(c-pp.D.sqlite3-bundler-friendly) -Dtarget=node", 0},

	{/* The wasmfs build is optional, untested, unsupported, and
	** needs to be invoked conditionally using info we don't have
	** here. */
	"sqlite3-wasmfs", "esm" ,
	LIBMODE_WASMFS \| LIBMODE_ESM \| LIBMODE_UNSUPPORTED,
	"sqlite3-wasmfs.mjs",
	"$(c-pp.D.sqlite3-bundler-friendly) -Dwasmfs",
	"-sEXPORT_ES6 -sUSE_ES6_IMPORT_META"},

	{/End-of-list sentinel/0,0,0,0,0,0}
	};

	/*
	** Emits common vars needed by the rest of the emitted code (but not
	** needed by makefile code outside of these generated pieces).
	*/
	static void mk_prologue(void){
	/* A 0-terminated list of makefile vars which we expect to have been
	** set up by this point in the build process. There are some which
	** we can't check here because they are not defined until after
	** these rules are included, but this set covers the basics. */
	char const * aRequiredVars[] = {
	"dir.top",
	"dir.api", "dir.dout", "dir.tmp",
	"sqlite3-license-version.js",
	"MAKEFILE", "MAKEFILE_LIST",
	/* Fiddle... */
	"dir.fiddle", "dir.fiddle-debug",
	"MAKEFILE.fiddle",
	"EXPORTED_FUNCTIONS.fiddle",
	/"just-testing",/
	0
	};
	char const * zVar;
	int i;
	pf("%s# Build setup sanity checks...\n", zBanner);
	for( i = 0; (zVar = aRequiredVars[i]); ++i ){
	pf("ifeq (,$(%s))\n", zVar);
	pf(" $(error build process error: expecting make var $$(%s) to "
	"have been set up by now)\n", zVar);
	ps("endif");
	}
	pf("%s", zBanner);
	ps("# extern-post-js* and extern-pre-js* are files for use with");
	ps("# Emscripten's --extern-pre-js and --extern-post-js flags.");
	ps("extern-pre-js.js = $(dir.api)/extern-pre-js.js");
	ps("extern-post-js.js.in = $(dir.api)/extern-post-js.c-pp.js");
	ps("# Emscripten flags for --[extern-][pre\|post]-js=... for the");
	ps("# various builds.");
	ps("pre-post-common.flags = --extern-pre-js=$(sqlite3-license-version.js)");
	ps("# pre-post-jses.deps.* = a list of dependencies for the\n"
	"# --[extern-][pre/post]-js files.");
	ps("pre-post-jses.deps.common = $(extern-pre-js.js) $(sqlite3-license-version.js)");

	{
	/* SQLITE.CALL.WASM-OPT = shell code to run $(1) (source wasm file
	** name) through $(bin.wasm-opt) */
	const char * zOptFlags =
	/*
	** Flags for wasm-opt. It has many, many, MANY "passes" options
	** and the ones which appear here were selected solely on the
	** basis of trial and error.
	**
	** All wasm file size savings/costs mentioned below are based on
	** the vanilla build of sqlite3.wasm with -Oz (our shipping
	** configuration). Comments like "saves nothing" may not be
	** technically correct: "nothing" means "some neglible amount."
	**
	** Note that performance gains/losses are _not_ taken into
	** account here: only wasm file size.
	*/
	"--enable-bulk-memory-opt " /* required */
	"--all-features " /* required */
	"--post-emscripten " /* Saves roughly 12kb */
	"--strip-debug " /* We already wasm-strip, but in
	** case this environment has no
	** wasm-strip... */
	/*
	** The rest are trial-and-error. See wasm-opt --help and search
	** for "Optimization passes" to find the full list.
	**
	** With many flags this gets unusuably slow.
	*/
	/"--converge " saves nothing for the options we're using /
	/"--dce " saves nothing /
	/"--directize " saves nothing /
	/*"--gsi " no: requires --closed-world flag, which does not
	** sound like something we want. */
	/"--gufa --gufa-cast-all --gufa-optimizing " costs roughly 2kb /
	/"--heap-store-optimization " saves nothing /
	/"--heap2local " saves nothing /
	//"--inlining --inlining-optimizing " costs roughly 3kb */
	"--local-cse " /* saves roughly 1kb */
	/"--once-reduction " saves nothing /
	/"--remove-memory-init " presumably a performance tweak /
	/"--remove-unused-names " saves nothing /
	/"--safe-heap "/
	/"--vacuum " saves nothing /
	;
	ps("ifeq (,$(bin.wasm-opt))");
	ps("define SQLITE.CALL.WASM-OPT");
	ps("echo 'wasm-opt not available for $(1)'");
	ps("endef");
	ps("else");
	ps("define SQLITE.CALL.WASM-OPT");
	pf("echo -n 'Before wasm-opt:'; ls -l $(1);\\\n"
	"\trm -f wasm-opt-tmp.wasm;\\\n"
	/* It's very likely that the set of wasm-opt flags varies from
	** version to version, so we'll ignore any errors here. */
	"\tif $(bin.wasm-opt) $(1) -o wasm-opt-tmp.wasm \\\n"
	"\t\t%s; then \\\n"
	"\t\tmv wasm-opt-tmp.wasm $(1); \\\n"
	"\t\techo -n 'After wasm-opt: '; \\\n"
	"\t\tls -l $(1); \\\n"
	"\telse \\\n"
	"\t\techo 'WARNING: ignoring wasm-opt failure for $(1)'; \\\n"
	"\tfi\n",
	zOptFlags
	);
	ps("endef");
	ps("endif");
	}
	}

	/*
	** Emits makefile code for setting up values for the --pre-js=FILE,
	** --post-js=FILE, and --extern-post-js=FILE emcc flags, as well as
	** populating those files.
	*/
	static void mk_pre_post(const char zName / build name */,
	const char zMode / build mode */,
	const char zCmppD / optional -D flags for c-pp for the
	** --pre/--post-js files. */){
	/* Very common printf() args combo. */
	#define zNM zName, zMode

	pf("%s# Begin --pre/--post flags for %s-%s\n", zBanner, zNM);
	pf("c-pp.D.%s-%s = %s\n", zNM, zCmppD ? zCmppD : "");
	pf("pre-post-%s-%s.flags ?=\n", zNM);

	/* --pre-js=... */
	pf("pre-js.js.%s-%s = $(dir.tmp)/pre-js.%s-%s.js\n",
	zNM, zNM);
	pf("$(pre-js.js.%s-%s): $(MAKEFILE_LIST) $(sqlite3-license-version.js)\n", zNM);
	#if 1
	pf("$(eval $(call SQLITE.CALL.C-PP.FILTER,$(pre-js.js.in),$(pre-js.js.%s-%s),"
	"$(c-pp.D.%s-%s)))\n", zNM, zNM);
	#else
	/* This part is needed if/when we re-enable the custom
	** Module.instantiateModule() impl in api/pre-js.c-pp.js. */
	pf("pre-js.js.%s-%s.intermediary = $(dir.tmp)/pre-js.%s-%s.intermediary.js\n",
	zNM, zNM);
	pf("$(eval $(call SQLITE.CALL.C-PP.FILTER,$(pre-js.js.in),$(pre-js.js.%s-%s.intermediary),"
	"$(c-pp.D.%s-%s) -Dcustom-Module.instantiateModule))\n", zNM, zNM);
	pf("$(pre-js.js.%s-%s): $(pre-js.js.%s-%s.intermediary)\n", zNM, zNM);
	pf("\tcp $(pre-js.js.%s-%s.intermediary) $@\n", zNM);

	/* Amend $(pre-js.js.zName-zMode) for all targets except the plain
	** "sqlite3" and the "sqlite3-wasmfs" builds... */
	if( 0!=strcmp("sqlite3-wasmfs", zName)
	&& 0!=strcmp("sqlite3", zName) ){
	#error "This part ^^^ is needs adapting for use with the LIBMODE_... flags"
	pf("\t@echo 'Module[xNameOfInstantiateWasm].uri = "
	"\"%s.wasm\";' >> $@\n", zName);
	}
	#endif

	/* --post-js=... */
	pf("post-js.js.%s-%s = $(dir.tmp)/post-js.%s-%s.js\n", zNM, zNM);
	pf("$(eval $(call SQLITE.CALL.C-PP.FILTER,$(post-js.js.in),"
	"$(post-js.js.%s-%s),$(c-pp.D.%s-%s)))\n", zNM, zNM);

	/* --extern-post-js=... */
	pf("extern-post-js.js.%s-%s = $(dir.tmp)/extern-post-js.%s-%s.js\n", zNM, zNM);
	pf("$(eval $(call SQLITE.CALL.C-PP.FILTER,$(extern-post-js.js.in),$(extern-post-js.js.%s-%s),"
	"$(c-pp.D.%s-%s)))\n", zNM, zNM);

	/* Combined flags for use with emcc... */
	pf("pre-post-common.flags.%s-%s = "
	"$(pre-post-common.flags) "
	"--post-js=$(post-js.js.%s-%s) "
	"--extern-post-js=$(extern-post-js.js.%s-%s)\n", zNM, zNM, zNM);

	pf("pre-post-%s-%s.flags += $(pre-post-common.flags.%s-%s) "
	"--pre-js=$(pre-js.js.%s-%s)\n", zNM, zNM, zNM);

	/* Set up deps... */
	pf("pre-post-jses.%s-%s.deps = $(pre-post-jses.deps.common) "
	"$(post-js.js.%s-%s) $(extern-post-js.js.%s-%s)\n",
	zNM, zNM, zNM);
	pf("pre-post-%s-%s.deps = $(pre-post-jses.%s-%s.deps) $(dir.tmp)/pre-js.%s-%s.js\n",
	zNM, zNM, zNM);
	pf("# End --pre/--post flags for %s-%s%s", zNM, zBanner);
	#undef zNM
	}

	/*
	** Emits rules for the fiddle builds.
	*/
	static void mk_fiddle(void){
	int i = 0;

	mk_pre_post("fiddle-module","vanilla", 0);
	for( ; i < 2; ++i ){
	/* 0==normal, 1==debug */
	const char *zTail = i ? ".debug" : "";
	const char *zDir = i ? "$(dir.fiddle-debug)" : "$(dir.fiddle)";

	pf("%s# Begin fiddle%s\n", zBanner, zTail);
	pf("fiddle-module.js%s = %s/fiddle-module.js\n", zTail, zDir);
	pf("fiddle-module.wasm%s = "
	"$(subst .js,.wasm,$(fiddle-module.js%s))\n", zTail, zTail);
	pf("$(fiddle-module.js%s):%s $(MAKEFILE_LIST) $(MAKEFILE.fiddle) "
	"$(EXPORTED_FUNCTIONS.fiddle) "
	"$(fiddle.cses) $(pre-post-fiddle-module-vanilla.deps) "
	"$(SOAP.js)\n",
	zTail, (i ? " $(fiddle-module.js)" : ""));
	if( 1==i ){/fiddle.debug/
	pf("\t@test -d \"$(dir $@)\" \|\| mkdir -p \"$(dir $@)\"\n");
	}
	pf("\t$(bin.emcc) -o $@ $(fiddle.emcc-flags%s) "
	"$(pre-post-fiddle-module-vanilla.flags) $(fiddle.cses)\n",
	zTail);
	pf("\t$(maybe-wasm-strip) $(fiddle-module.wasm%s)\n", zTail);
	pf("\t@cp -p $(SOAP.js) $(dir $@)\n");
	if( 1==i ){/fiddle.debug/
	pf("\tcp -p $(dir.fiddle)/index.html "
	"$(dir.fiddle)/fiddle.js "
	"$(dir.fiddle)/fiddle-worker.js "
	"$(dir $@)\n");
	}
	pf("\t@for i in %s/.js %s/.html %s/.wasm; do \\\n"
	"\t\ttest -f $${i} \|\| continue; \\\n"
	"\t\tgzip < $${i} > $${i}.gz; \\\n"
	"\tdone\n", zDir, zDir, zDir);
	if( 0==i ){
	ps("fiddle: $(fiddle-module.js)");
	}else{
	ps("fiddle-debug: $(fiddle-module-debug.js)");
	}
	pf("# End fiddle%s%s", zTail, zBanner);
	}
	}

	/*
	** Emits makefile code for one build of the library, primarily defined
	** by the combination of zName and zMode, each of which must be values
	** from JS_BUILD_NAMES resp. JS_BUILD_MODES.
	*/
	static void mk_lib_mode(const BuildDef * pB){
	char aOutBuf[1024] = {0};
	const char * zWasmOut = "$(basename $@).wasm"
	/* The various targets named X.js or X.mjs (zJsOut) also generate
	** X.wasm, and we need that part of the name to perform some
	** post-processing after Emscripten generates X.wasm. */;
	assert( pB->zName );
	assert( pB->zMode );
	assert( pB->zJsOut );
	/* Very common printf() args combo. */
	#define zNM pB->zName, pB->zMode

	pf("%s# Begin build [%s-%s]. flags=0x%02x\n", zBanner, zNM, pB->flags);
	pf("# zJsOut=%s\n# zCmppD=%s\n", pB->zJsOut,
	pB->zCmppD ? pB->zCmppD : "<none>");
	pf("$(info Setting up build [%s-%s]: %s)\n", zNM, pB->zJsOut);
	mk_pre_post(zNM, pB->zCmppD);

	snprintf(aOutBuf, sizeof(aOutBuf), "$(dir.tmp)/%s-%s", zNM);

	/* Set up build-specific output dir. Several of the builds generate
	** a file named sqlite3.wasm, which precludes us building them in
	** parallel. We use a build-specific dir to enable parallization of
	** those builds. All such builds will generate a byte-for-byte
	** identical sqlite3.wasm so long as all Emscripten-related flags
	** which influence that file are the same (i.e. where pB->zEmcc is
	** the same), which is the case for most of the affected builds. */
	pf("dir.tmp.%s-%s = %s\n", zNM, aOutBuf);
	pf("$(dir.tmp.%s-%s):\n\tmkdir -p $@\n", zNM);
	#if 0
	/* We don't need to add cleanup rules so long as these dirs are
	** under $(dir.tmp), as that dir will be cleaned up by 'make
	** clean'. If these dirs move somewhere else, we'll want to add a
	** rule like...*/
	pf("clean-%s-%s:\n\trm -fr $(dir.tmp.%s-%s)\n"
	"clean: clean-%s-%s\n", zNM, zNM, zNM);
	#endif

	pf("\nemcc.flags.%s.%s ?=\n", zNM);
	if( pB->zEmcc && pB->zEmcc[0] ){
	pf("emcc.flags.%s.%s += %s\n", zNM, pB->zEmcc);
	}

	/* target pB->zJsOut */
	pf("$(dir.tmp.%s-%s)/%s: "
	"$(dir.tmp.%s-%s) "
	"$(MAKEFILE_LIST) $(sqlite3-wasm.cfiles) $(EXPORTED_FUNCTIONS.api) "
	"$(pre-post-%s-%s.deps) "
	"$(sqlite3-api.ext.jses)"
	/* ^^^ maintenance reminder: we set these as deps so that they
	** get copied into place early. That allows the developer to
	** reload the base-most test pages while the later-stage builds
	** are still compiling, which is especially helpful when running
	** builds with long build times (like -Oz). */
	"\n",
	zNM, pB->zJsOut, zNM, zNM);
	pf("\t@echo \"Building [%s-%s] %s ...\"\n", zNM, pB->zJsOut);
	pf("\t$(bin.emcc) -o $@ $(emcc_opt_full) $(emcc.flags) \\\n");
	pf("\t\t$(emcc.jsflags) -sENVIRONMENT=$(emcc.environment.%s) \\\n",
	pB->zMode);
	pf("\t\t$(pre-post-%s-%s.flags) \\\n", zNM);
	pf("\t\t$(emcc.flags.%s) $(emcc.flags.%s.%s) \\\n", pB->zName, zNM);
	pf("\t\t$(cflags.common) $(SQLITE_OPT) \\\n"
	"\t\t$(cflags.%s) $(cflags.%s.%s) \\\n"
	"\t\t$(cflags.wasm_extra_init) $(sqlite3-wasm.cfiles)\n", pB->zName, zNM);
	if( (LIBMODE_ESM & pB->flags) \|\| (LIBMODE_NODEJS & pB->flags) ){
	/* TODO? Replace this $(call) with the corresponding makefile
	** code. OTOH, we also use this $(call) in the speedtest1-wasmfs
	** build, which is not part of the rules emitted by this
	** program. */
	pf("\t@$(call SQLITE.CALL.xJS.ESM-EXPORT-DEFAULT,1,%d)\n",
	(LIBMODE_WASMFS & pB->flags) ? 1 : 0);
	}
	pf("\t@chmod -x %s; \\\n"
	"\t\t$(maybe-wasm-strip) %s;\n",
	zWasmOut, zWasmOut)
	/* For whatever reasons, .wasm files get built with their +x bit
	** set. That upsets althttpd, which uses +x as an indication that
	** the file is a CGI script. There's no apparent useful reason to
	** have +x set on these, so we -x them. */;
	pf("\t@$(call SQLITE.CALL.WASM-OPT,%s)\n", zWasmOut);
	pf(/* Our JS code installs bindings of each WASM export. The
	** generated Emscripten JS file does the same using its own
	** framework, but we don't use those results and can speed up lib
	** init, and reduce memory cost a bit, by stripping them out. Of
	** of this writing, this strips approximately 25kb of JS code. */
	"\t@sed -i -e '/^.= _sqlite.= createExportWrapper/d' $@ \|\| exit; \\\n"
	/* ^^^^^^ reminder: Mac/BSD sed has no -i flag */
	"\t\techo 'Stripped out createExportWrapper() parts.'\n");
	/*
	** The above $(bin.emcc) call will write pB->zJsOut and will create
	** a like-named .wasm file (zWasmOut). That .wasm file name gets
	** hard-coded into zJsOut so we need to, for some cases, patch
	** zJsOut to use the name sqlite3.wasm instead. Note that the
	** resulting .wasm file is identical for all builds for which
	** pB->zEmcc is empty.
	*/
	if( (LIBMODE_PATCH_WASM_NAME & pB->flags) ){
	pf("\t@echo 'Patching $@ for %s.wasm...'; \\\n", pB->zName);
	pf("\t\trm -f %s; \\\n", zWasmOut);
	pf("\t\tsed -i -e 's/%s-%s.wasm/%s.wasm/g' $@ \|\| exit;\n",
	/* ^^^^^^ reminder: Mac/BSD sed has no -i flag but this
	** build process explicitly requires a Linux system. */
	zNM, pB->zName);
	pf("\t@ls -la $@\n");
	if( LIBMODE_BUNDLER_FRIENDLY & pB->flags ){
	/* Avoid a 3rd occurrence of the bug fixed by 65798c09a00662a3,
	** which was (in two cases) caused by makefile refactoring and
	** not recognized until after a release was made with the broken
	** sqlite3-bundler-friendly.mjs (which is used by the npm
	** subproject but is otherwise untested/unsupported): */
	pf("\t@if grep -e '^ *importScripts(' $@; "
	"then echo 'ERROR: bug fixed in 65798c09a00662a3 has re-appeared'; "
	"exit 1; fi;\n");
	}
	}else{
	pf("\t@ls -la %s $@\n", zWasmOut);
	}
	pf("\n$(dir.dout)/%s: $(dir.tmp.%s-%s)/%s\n", pB->zJsOut, zNM, pB->zJsOut);
	pf("\t@cp -p $(dir.tmp.%s-%s)/%s $(dir.dout)/.\n", zNM, pB->zJsOut);
	if( (LIBMODE_SQLITE3_WASM & pB->flags) ){
	pf("\t@cp -p $(dir.tmp.%s-%s)/*.wasm $(dir.dout)/.\n", zNM);
	}
	if( 0==(LIBMODE_UNSUPPORTED & pB->flags) ){
	pf("all: $(dir.dout)/%s\n", pB->zJsOut);
	}
	pf("%s-%s: $(dir.tmp.%s-%s)/%s\n", zNM, zNM, pB->zJsOut);
	pf("# End build [%s-%s]%s", zNM, zBanner);
	#undef zNM
	}

	int main(void){
	int rc = 0;
	const BuildDef *pB = &aBuildDefs[0];
	pf("# What follows was GENERATED by %s. Edit at your own risk.\n", __FILE__);
	mk_prologue();
	for( ; pB->zName; ++pB ){
	mk_lib_mode( pB );
	}
	mk_fiddle();
	mk_pre_post("speedtest1","vanilla", 0);
	mk_pre_post("speedtest1-wasmfs","esm",
	"$(c-pp.D.sqlite3-bundler-friendly) -Dwasmfs");
	return rc;
	}