Merge branch 'dscho/gcc-8-gfw'

This backports several patch series from Git for Windows' `master` to
make things compile with GCC v8.x, as that will soon be the default for
Git for Windows (and is already the current setup on this developer's
machine).

Author: dscho

compat/obstack.c

@@ -112,15 +112,15 @@ compat_symbol (libc, _obstack_compat, _obstack, GLIBC_2_0);
 
 # define CALL_CHUNKFUN(h, size) \
   (((h) -> use_extra_arg) \
-   ? (*(h)->chunkfun) ((h)->extra_arg, (size)) \
-   : (*(struct _obstack_chunk *(*) (long)) (h)->chunkfun) ((size)))
+   ? (*(h)->chunkfun.extra) ((h)->extra_arg, (size)) \
+   : (*(h)->chunkfun.plain) ((size)))
 
 # define CALL_FREEFUN(h, old_chunk) \
   do { \
     if ((h) -> use_extra_arg) \
-      (*(h)->freefun) ((h)->extra_arg, (old_chunk)); \
+      (*(h)->freefun.extra) ((h)->extra_arg, (old_chunk)); \
     else \
-      (*(void (*) (void *)) (h)->freefun) ((old_chunk)); \
+      (*(h)->freefun.plain) ((old_chunk)); \
   } while (0)
 
 
@@ -159,8 +159,8 @@ _obstack_begin (struct obstack *h,
       size = 4096 - extra;
     }
 
-  h->chunkfun = (struct _obstack_chunk * (*)(void *, long)) chunkfun;
-  h->freefun = (void (*) (void *, struct _obstack_chunk *)) freefun;
+  h->chunkfun.plain = chunkfun;
+  h->freefun.plain = freefun;
   h->chunk_size = size;
   h->alignment_mask = alignment - 1;
   h->use_extra_arg = 0;
@@ -206,8 +206,9 @@ _obstack_begin_1 (struct obstack *h, int size, int alignment,
       size = 4096 - extra;
     }
 
-  h->chunkfun = (struct _obstack_chunk * (*)(void *,long)) chunkfun;
-  h->freefun = (void (*) (void *, struct _obstack_chunk *)) freefun;
+  h->chunkfun.extra = (struct _obstack_chunk * (*)(void *,long)) chunkfun;
+  h->freefun.extra = (void (*) (void *, struct _obstack_chunk *)) freefun;
+
   h->chunk_size = size;
   h->alignment_mask = alignment - 1;
   h->extra_arg = arg;

compat/obstack.h

@@ -160,11 +160,15 @@ struct obstack		/* control current object in current chunk */
     void *tempptr;
   } temp;			/* Temporary for some macros.  */
   int   alignment_mask;		/* Mask of alignment for each object. */
-  /* These prototypes vary based on `use_extra_arg', and we use
-     casts to the prototypeless function type in all assignments,
-     but having prototypes here quiets -Wstrict-prototypes.  */
-  struct _obstack_chunk *(*chunkfun) (void *, long);
-  void (*freefun) (void *, struct _obstack_chunk *);
+  /* These prototypes vary based on `use_extra_arg'. */
+  union {
+    void *(*plain) (long);
+    struct _obstack_chunk *(*extra) (void *, long);
+  } chunkfun;
+  union {
+    void (*plain) (void *);
+    void (*extra) (void *, struct _obstack_chunk *);
+  } freefun;
   void *extra_arg;		/* first arg for chunk alloc/dealloc funcs */
   unsigned use_extra_arg:1;	/* chunk alloc/dealloc funcs take extra arg */
   unsigned maybe_empty_object:1;/* There is a possibility that the current
@@ -235,10 +239,10 @@ extern void (*obstack_alloc_failed_handler) (void);
 		    (void (*) (void *, void *)) (freefun), (arg))
 
 #define obstack_chunkfun(h, newchunkfun) \
-  ((h) -> chunkfun = (struct _obstack_chunk *(*)(void *, long)) (newchunkfun))
+  ((h)->chunkfun.extra = (struct _obstack_chunk *(*)(void *, long)) (newchunkfun))
 
 #define obstack_freefun(h, newfreefun) \
-  ((h) -> freefun = (void (*)(void *, struct _obstack_chunk *)) (newfreefun))
+  ((h)->freefun.extra = (void (*)(void *, struct _obstack_chunk *)) (newfreefun))
 
 #define obstack_1grow_fast(h,achar) (*((h)->next_free)++ = (achar))
 

compat/poll/poll.c

@@ -149,7 +149,7 @@ win32_compute_revents (HANDLE h, int *p_sought)
     case FILE_TYPE_PIPE:
       if (!once_only)
 	{
-	  NtQueryInformationFile = (PNtQueryInformationFile)
+	  NtQueryInformationFile = (PNtQueryInformationFile)(void (*)(void))
 	    GetProcAddress (GetModuleHandleA ("ntdll.dll"),
 			    "NtQueryInformationFile");
 	  once_only = TRUE;

compat/win32/exit-process.h

@@ -130,7 +130,8 @@ static int exit_process(HANDLE process, int exit_code)
 			HINSTANCE kernel32 = GetModuleHandleA("kernel32");
 			if (!kernel32)
 				die("BUG: cannot find kernel32");
-			exit_process_address = (LPTHREAD_START_ROUTINE)
+			exit_process_address =
+				(LPTHREAD_START_ROUTINE)(void (*)(void))
 				GetProcAddress(kernel32, "ExitProcess");
 			initialized = 1;
 		}

kwset.c

@@ -38,7 +38,13 @@
 #include "compat/obstack.h"
 
 #define NCHAR (UCHAR_MAX + 1)
-#define obstack_chunk_alloc xmalloc
+/* adapter for `xmalloc()`, which takes `size_t`, not `long` */
+static void *obstack_chunk_alloc(long size)
+{
+	if (size < 0)
+		BUG("Cannot allocate a negative amount: %ld", size);
+	return xmalloc(size);
+}
 #define obstack_chunk_free free
 
 #define U(c) ((unsigned char) (c))