Don't permalloc the pkgimgs unnecessarily

src/staticdata.c

@@ -71,6 +71,7 @@ External links:
 */
 #include <stdlib.h>
 #include <string.h>
+#include <stdbool.h>
 #include <stdio.h> // printf
 #include <inttypes.h> // PRIxPTR
 
@@ -3199,7 +3200,7 @@ static jl_value_t *jl_validate_cache_file(ios_t *f, jl_array_t *depmods, uint64_
 }
 
 // TODO?: refactor to make it easier to create the "package inspector"
-static jl_value_t *jl_restore_package_image_from_stream(ios_t *f, jl_image_t *image, jl_array_t *depmods, int complete)
+static jl_value_t *jl_restore_package_image_from_stream(ios_t *f, jl_image_t *image, jl_array_t *depmods, int complete, bool needs_permalloc)
 {
     uint64_t checksum = 0;
     int64_t dataendpos = 0;
@@ -3218,18 +3219,26 @@ static jl_value_t *jl_restore_package_image_from_stream(ios_t *f, jl_image_t *im
     arraylist_t ccallable_list;
     JL_GC_PUSH8(&restored, &init_order, &extext_methods, &new_specializations, &method_roots_list, &ext_targets, &edges, &cachesizes_sv);
 
-    { // make a permanent in-memory copy of f (excluding the header)
+    { // make a permanent in-memory copy of f (excluding the header) if needed
         ios_bufmode(f, bm_none);
         JL_SIGATOMIC_BEGIN();
         size_t len = dataendpos - datastartpos;
-        char *sysimg = (char*)jl_gc_perm_alloc(len, 0, 64, 0);
+        char *sysimg;
+        bool success = !needs_permalloc;
         ios_seek(f, datastartpos);
-        if (ios_readall(f, sysimg, len) != len || jl_crc32c(0, sysimg, len) != (uint32_t)checksum) {
-            restored = jl_get_exceptionf(jl_errorexception_type, "Error reading system image file.");
+        if (needs_permalloc)
+            sysimg = (char*)jl_gc_perm_alloc(len, 0, 64, 0);
+        else
+            sysimg = &f->buf[f->bpos];
+        if (needs_permalloc)
+            success = ios_readall(f, sysimg, len) == len;
+        if (!success || jl_crc32c(0, sysimg, len) != (uint32_t)checksum) {
+            restored = jl_get_exceptionf(jl_errorexception_type, "Error reading package image file.");
             JL_SIGATOMIC_END();
         }
         else {
-            ios_close(f);
+            if (needs_permalloc)
+                ios_close(f);
             ios_static_buffer(f, sysimg, len);
             htable_new(&new_code_instance_validate, 0);
             pkgcachesizes cachesizes;
@@ -3275,11 +3284,11 @@ static void jl_restore_system_image_from_stream(ios_t *f, jl_image_t *image)
     jl_restore_system_image_from_stream_(f, image, NULL, checksum, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL);
 }
 
-JL_DLLEXPORT jl_value_t *jl_restore_incremental_from_buf(const char *buf, jl_image_t *image, size_t sz, jl_array_t *depmods, int complete)
+JL_DLLEXPORT jl_value_t *jl_restore_incremental_from_buf(const char *buf, jl_image_t *image, size_t sz, jl_array_t *depmods, int complete, bool needs_permalloc)
 {
     ios_t f;
     ios_static_buffer(&f, (char*)buf, sz);
-    jl_value_t *ret = jl_restore_package_image_from_stream(&f, image, depmods, complete);
+    jl_value_t *ret = jl_restore_package_image_from_stream(&f, image, depmods, complete, needs_permalloc);
     ios_close(&f);
     return ret;
 }
@@ -3292,7 +3301,7 @@ JL_DLLEXPORT jl_value_t *jl_restore_incremental(const char *fname, jl_array_t *d
             "Cache file \"%s\" not found.\n", fname);
     }
     jl_image_t pkgimage = {};
-    jl_value_t *ret = jl_restore_package_image_from_stream(&f, &pkgimage, depmods, complete);
+    jl_value_t *ret = jl_restore_package_image_from_stream(&f, &pkgimage, depmods, complete, true);
     ios_close(&f);
     return ret;
 }
@@ -3392,7 +3401,7 @@ JL_DLLEXPORT jl_value_t *jl_restore_package_image_from_file(const char *fname, j
         }
     #endif
 
-    jl_value_t* mod = jl_restore_incremental_from_buf(pkgimg_data, &pkgimage, *plen, depmods, complete);
+    jl_value_t* mod = jl_restore_incremental_from_buf(pkgimg_data, &pkgimage, *plen, depmods, complete, false);
 
     return mod;
 }

test/loading.jl

@@ -1066,5 +1066,26 @@ end
     end
 end
 
+@testset "--pkgimages=no" begin
+    old_depot_path = copy(DEPOT_PATH)
+    try
+        tmp = mktempdir()
+        push!(empty!(DEPOT_PATH), joinpath(tmp, "depot"))
+
+        proj = joinpath(@__DIR__, "project", "Extensions", "HasDepWithExtensions.jl")
+        for compile in (`--pkgimages=no`, `--pkgimages=no`) # Once when requiring precomilation, once where it is already precompiled
+            cmd = `$(Base.julia_cmd()) $compile --project=$proj --startup-file=no -e '
+                begin
+                using HasExtensions
+                using HasDepWithExtensions
+                end
+            '`
+            @test success(cmd)
+        end
+    finally
+        copy!(DEPOT_PATH, old_depot_path)
+    end
+end
+
 empty!(Base.DEPOT_PATH)
 append!(Base.DEPOT_PATH, original_depot_path)