Comment 76 for bug 1751460

(In reply to Michael Catanzaro from comment #18)
> Here's a debug patch:

It's missing <cstring> include for strerror..

diff -up webkitgtk-2.20.0/Source/bmalloc/bmalloc/VMAllocate.h.bmalloc_debug webkitgtk-2.20.0/Source/bmalloc/bmalloc/VMAllocate.h
--- webkitgtk-2.20.0/Source/bmalloc/bmalloc/VMAllocate.h.bmalloc_debug 2018-02-19 08:45:33.000000000 +0100
+++ webkitgtk-2.20.0/Source/bmalloc/bmalloc/VMAllocate.h 2018-03-14 09:26:14.977674938 +0100
@@ -35,6 +35,10 @@
 #include <sys/mman.h>
 #include <unistd.h>

+#include <cstdio>
+#include <errno.h>
+#include <cstring>
+
 #if BOS(DARWIN)
 #include <mach/vm_page_size.h>
 #include <mach/vm_statistics.h>
@@ -122,8 +126,10 @@ inline void* tryVMAllocate(size_t vmSize
 {
     vmValidate(vmSize);
     void* result = mmap(0, vmSize, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON | BMALLOC_NORESERVE, BMALLOC_VM_TAG, 0);
- if (result == MAP_FAILED)
- return nullptr;
+ if (result == MAP_FAILED) {
+ fprintf(stderr, "%s: mmap failed: vmSize=%zu errno=%d (%s)", __FUNCTION__, vmSize, errno, strerror(errno));
+ return nullptr;
+ }
     return result;
 }