empathicqubit/cc65
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Global uninitialized variable is only a tentative definition.

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Closes #204
This commit is contained in:
Piotr Fusik 2017-02-13 21:04:45 +01:00
parent 1f12a06f7c
commit 730d01a25f
1 changed files with 30 additions and 25 deletions
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55
src/cc65/compile.c
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@ -154,7 +154,7 @@ static void Parse (void)
(Decl.StorageClass & (SC_EXTERN|SC_STATIC)) == SC_STATIC)) {
/* We will allocate storage */
Decl.StorageClass |= SC_STORAGE | SC_DEF;
Decl.StorageClass |= SC_STORAGE;
}
/* If this is a function declarator that is not followed by a comma
@ -187,6 +187,9 @@ static void Parse (void)
/* Allow initialization */
if (CurTok.Tok == TOK_ASSIGN) {
/* This is a definition */
Entry->Flags |= SC_DEF;
/* We cannot initialize types of unknown size, or
** void types in ISO modes.
*/
@ -234,18 +237,14 @@ static void Parse (void)
Entry->Flags &= ~(SC_STORAGE | SC_DEF);
}
/* Allocate storage if it is still needed */
if (Entry->Flags & SC_STORAGE) {
/* Switch to the BSS segment */
g_usebss ();
/* Define a label */
g_defgloblabel (Entry->Name);
/* Allocate space for uninitialized variable */
g_res (Size);
}
/* A global (including static) uninitialized variable
** is only a tentative definition. For example, this is valid:
** int i;
** int i;
** static int j;
** static int j = 42;
** Code for these will be generated in FinishCompile.
*/
}
}
@ -300,7 +299,7 @@ void Compile (const char* FileName)
struct tm* TM;
/* Since strftime is locale dependent, we need the abbreviated month names
** in english.
** in English.
*/
static const char MonthNames[12][4] = {
"Jan", "Feb", "Mar", "Apr", "May", "Jun",
@ -397,20 +396,26 @@ void Compile (const char* FileName)
void FinishCompile (void)
/* Emit literals, externals, debug info, do cleanup and optimizations */
{
SymTable* SymTab;
SymEntry* Func;
SymEntry* Entry;
/* Walk over all functions, doing cleanup, optimizations ... */
SymTab = GetGlobalSymTab ();
Func = SymTab->SymHead;
while (Func) {
if (SymIsOutputFunc (Func)) {
/* Walk over all global symbols:
** - for functions do cleanup, optimizations ...
** - generate code for uninitialized global variables
*/
for (Entry = GetGlobalSymTab ()->SymHead; Entry; Entry = Entry->NextSym) {
if (SymIsOutputFunc (Entry)) {
/* Function which is defined and referenced or extern */
MoveLiteralPool (Func->V.F.LitPool);
CS_MergeLabels (Func->V.F.Seg->Code);
RunOpt (Func->V.F.Seg->Code);
MoveLiteralPool (Entry->V.F.LitPool);
CS_MergeLabels (Entry->V.F.Seg->Code);
RunOpt (Entry->V.F.Seg->Code);
} else if ((Entry->Flags & (SC_STORAGE | SC_DEF | SC_STATIC)) == (SC_STORAGE | SC_STATIC)) {
/* Tentative definition of uninitialized global variable */
g_usebss ();
g_defgloblabel (Entry->Name);
g_res (SizeOf (Entry->Type));
/* Mark as defined, so that it will be exported not imported */
Entry->Flags |= SC_DEF;
}
Func = Func->NextSym;
}
/* Output the literal pool */