diff --git a/contrib/elf2dmp/main.c b/contrib/elf2dmp/main.c
index cb28971789e4..c290781feb18 100644
--- a/contrib/elf2dmp/main.c
+++ b/contrib/elf2dmp/main.c
@@ -186,13 +186,13 @@ static void win_context_init_from_qemu_cpu_state(WinContext64 *ctx,
  * Finds paging-structure hierarchy base,
  * if previously set doesn't give access to kernel structures
  */
-static int fix_dtb(struct va_space *vs, QEMU_Elf *qe)
+static bool fix_dtb(struct va_space *vs, QEMU_Elf *qe)
 {
     /*
      * Firstly, test previously set DTB.
      */
     if (va_space_resolve(vs, SharedUserData)) {
-        return 0;
+        return true;
     }
 
     /*
@@ -206,7 +206,7 @@ static int fix_dtb(struct va_space *vs, QEMU_Elf *qe)
             va_space_set_dtb(vs, s->cr[3]);
             printf("DTB 0x%016"PRIx64" has been found from CPU #%zu"
                     " as system task CR3\n", vs->dtb, i);
-            return !(va_space_resolve(vs, SharedUserData));
+            return !!(va_space_resolve(vs, SharedUserData));
         }
     }
 
@@ -220,16 +220,16 @@ static int fix_dtb(struct va_space *vs, QEMU_Elf *qe)
         uint64_t *cr3 = va_space_resolve(vs, Prcb + 0x7000);
 
         if (!cr3) {
-            return 1;
+            return false;
         }
 
         va_space_set_dtb(vs, *cr3);
         printf("DirectoryTableBase = 0x%016"PRIx64" has been found from CPU #0"
                 " as interrupt handling CR3\n", vs->dtb);
-        return !(va_space_resolve(vs, SharedUserData));
+        return !!(va_space_resolve(vs, SharedUserData));
     }
 
-    return 1;
+    return true;
 }
 
 static void try_merge_runs(struct pa_space *ps,
@@ -268,9 +268,10 @@ static void try_merge_runs(struct pa_space *ps,
     }
 }
 
-static int fill_header(WinDumpHeader64 *hdr, struct pa_space *ps,
-        struct va_space *vs, uint64_t KdDebuggerDataBlock,
-        KDDEBUGGER_DATA64 *kdbg, uint64_t KdVersionBlock, int nr_cpus)
+static bool fill_header(WinDumpHeader64 *hdr, struct pa_space *ps,
+                        struct va_space *vs, uint64_t KdDebuggerDataBlock,
+                        KDDEBUGGER_DATA64 *kdbg, uint64_t KdVersionBlock,
+                        int nr_cpus)
 {
     uint32_t *suite_mask = va_space_resolve(vs, SharedUserData +
             KUSD_OFFSET_SUITE_MASK);
@@ -283,12 +284,12 @@ static int fill_header(WinDumpHeader64 *hdr, struct pa_space *ps,
     QEMU_BUILD_BUG_ON(KUSD_OFFSET_PRODUCT_TYPE >= ELF2DMP_PAGE_SIZE);
 
     if (!suite_mask || !product_type) {
-        return 1;
+        return false;
     }
 
     if (!va_space_rw(vs, KdVersionBlock, &kvb, sizeof(kvb), 0)) {
         eprintf("Failed to extract KdVersionBlock\n");
-        return 1;
+        return false;
     }
 
     h = (WinDumpHeader64) {
@@ -333,7 +334,7 @@ static int fill_header(WinDumpHeader64 *hdr, struct pa_space *ps,
 
     *hdr = h;
 
-    return 0;
+    return true;
 }
 
 /*
@@ -379,8 +380,8 @@ static void fill_context(KDDEBUGGER_DATA64 *kdbg,
     }
 }
 
-static int pe_get_data_dir_entry(uint64_t base, void *start_addr, int idx,
-        void *entry, size_t size, struct va_space *vs)
+static bool pe_get_data_dir_entry(uint64_t base, void *start_addr, int idx,
+                                  void *entry, size_t size, struct va_space *vs)
 {
     const char e_magic[2] = "MZ";
     const char Signature[4] = "PE\0\0";
@@ -393,38 +394,38 @@ static int pe_get_data_dir_entry(uint64_t base, void *start_addr, int idx,
     QEMU_BUILD_BUG_ON(sizeof(*dos_hdr) >= ELF2DMP_PAGE_SIZE);
 
     if (memcmp(&dos_hdr->e_magic, e_magic, sizeof(e_magic))) {
-        return 1;
+        return false;
     }
 
     if (!va_space_rw(vs, base + dos_hdr->e_lfanew,
                      &nt_hdrs, sizeof(nt_hdrs), 0)) {
-        return 1;
+        return false;
     }
 
     if (memcmp(&nt_hdrs.Signature, Signature, sizeof(Signature)) ||
             file_hdr->Machine != 0x8664 || opt_hdr->Magic != 0x020b) {
-        return 1;
+        return false;
     }
 
     if (!va_space_rw(vs, base + data_dir[idx].VirtualAddress, entry, size, 0)) {
-        return 1;
+        return false;
     }
 
     printf("Data directory entry #%d: RVA = 0x%08"PRIx32"\n", idx,
             (uint32_t)data_dir[idx].VirtualAddress);
 
-    return 0;
+    return true;
 }
 
-static int write_dump(struct pa_space *ps,
-        WinDumpHeader64 *hdr, const char *name)
+static bool write_dump(struct pa_space *ps,
+                       WinDumpHeader64 *hdr, const char *name)
 {
     FILE *dmp_file = fopen(name, "wb");
     size_t i;
 
     if (!dmp_file) {
         eprintf("Failed to open output file \'%s\'\n", name);
-        return 1;
+        return false;
     }
 
     printf("Writing header to file...\n");
@@ -432,7 +433,7 @@ static int write_dump(struct pa_space *ps,
     if (fwrite(hdr, sizeof(*hdr), 1, dmp_file) != 1) {
         eprintf("Failed to write dump header\n");
         fclose(dmp_file);
-        return 1;
+        return false;
     }
 
     for (i = 0; i < ps->block_nr; i++) {
@@ -443,11 +444,11 @@ static int write_dump(struct pa_space *ps,
         if (fwrite(b->addr, b->size, 1, dmp_file) != 1) {
             eprintf("Failed to write block\n");
             fclose(dmp_file);
-            return 1;
+            return false;
         }
     }
 
-    return fclose(dmp_file);
+    return !fclose(dmp_file);
 }
 
 static bool pe_check_pdb_name(uint64_t base, void *start_addr,
@@ -457,8 +458,8 @@ static bool pe_check_pdb_name(uint64_t base, void *start_addr,
     IMAGE_DEBUG_DIRECTORY debug_dir;
     char pdb_name[sizeof(PDB_NAME)];
 
-    if (pe_get_data_dir_entry(base, start_addr, IMAGE_FILE_DEBUG_DIRECTORY,
-                &debug_dir, sizeof(debug_dir), vs)) {
+    if (!pe_get_data_dir_entry(base, start_addr, IMAGE_FILE_DEBUG_DIRECTORY,
+                               &debug_dir, sizeof(debug_dir), vs)) {
         eprintf("Failed to get Debug Directory\n");
         return false;
     }
@@ -546,7 +547,7 @@ int main(int argc, char *argv[])
     printf("CPU #0 CR3 is 0x%016"PRIx64"\n", state->cr[3]);
 
     va_space_create(&vs, &ps, state->cr[3]);
-    if (fix_dtb(&vs, &qemu_elf)) {
+    if (!fix_dtb(&vs, &qemu_elf)) {
         eprintf("Failed to find paging base\n");
         goto out_elf;
     }
@@ -611,14 +612,14 @@ int main(int argc, char *argv[])
         goto out_pdb;
     }
 
-    if (fill_header(&header, &ps, &vs, KdDebuggerDataBlock, kdbg,
-            KdVersionBlock, qemu_elf.state_nr)) {
+    if (!fill_header(&header, &ps, &vs, KdDebuggerDataBlock, kdbg,
+                     KdVersionBlock, qemu_elf.state_nr)) {
         goto out_kdbg;
     }
 
     fill_context(kdbg, &vs, &qemu_elf);
 
-    if (write_dump(&ps, &header, argv[2])) {
+    if (!write_dump(&ps, &header, argv[2])) {
         eprintf("Failed to save dump\n");
         goto out_kdbg;
     }
