Improve --enable-gcc-warnings for MinGW64

This partially reverts my 2016-05-30 patch.  Apparently MinGW64
still requires pacifications that GCC 7.1.1 x86-64 (Fedora 26)
does not.  Also, pacify tparam.c, which isn’t used on Fedora.
* lib-src/etags.c (process_file_name, TeX_commands):
* src/buffer.c (fix_overlays_before):
* src/data.c (Fmake_variable_buffer_local, cons_to_unsigned)
(cons_to_signed):
* src/editfns.c (Ftranslate_region_internal):
Prefer UNINIT to some stray value, as this simplifies
code-reading later.
* src/eval.c (CACHEABLE): New macro.
(internal_lisp_condition_case): Use it.
* src/tparam.c (tparam1): Use FALLTHROUGH to pacify GCC.

1 files changed, 3 insertions, 3 deletions

diff --git a/src/data.c b/src/data.c
index 87010e3fb28..c9818b6b20f 100644
--- a/src/data.c
+++ b/src/data.c
@@ -1823,7 +1823,7 @@ The function `default-value' gets the default value and `set-default' sets it.
   struct Lisp_Symbol *sym;
   struct Lisp_Buffer_Local_Value *blv = NULL;
   union Lisp_Val_Fwd valcontents;
-  bool forwarded = false;
+  bool forwarded UNINIT;
 
   CHECK_SYMBOL (variable);
   sym = XSYMBOL (variable);
@@ -2607,7 +2607,7 @@ uintmax_t
 cons_to_unsigned (Lisp_Object c, uintmax_t max)
 {
   bool valid = false;
-  uintmax_t val = max;
+  uintmax_t val UNINIT;
   if (INTEGERP (c))
     {
       valid = XINT (c) >= 0;
@@ -2661,7 +2661,7 @@ intmax_t
 cons_to_signed (Lisp_Object c, intmax_t min, intmax_t max)
 {
   bool valid = false;
-  intmax_t val = max;
+  intmax_t val UNINIT;
   if (INTEGERP (c))
     {
       val = XINT (c);