Also weaken libc and generic templates.

src/compiler/compiler_internal.h

@@ -1886,6 +1886,7 @@ extern const char *kw_at_jump;
 extern const char *kw_in;
 extern const char *kw_inout;
 extern const char *kw_len;
+extern const char *kw_libc;
 extern const char *kw_main;
 extern const char *kw_mainstub;
 extern const char *kw_memcmp;

src/compiler/llvm_codegen.c

@@ -51,8 +51,9 @@ static void diagnostics_handler(LLVMDiagnosticInfoRef ref, void *context)
 
 bool module_should_weaken(Module *module)
 {
+	if (module->generic_module) return true;
 	Module *top = module->top_module;
-	return top && top->name->module == kw_std;
+	return top && (top->name->module == kw_std || top->name->module == kw_libc);
 }
 
 static void gencontext_init(GenContext *context, Module *module, LLVMContextRef shared_context)

src/compiler/symtab.c

@@ -50,6 +50,7 @@ const char *kw_at_jump;
 const char *kw_in;
 const char *kw_inout;
 const char *kw_len;
+const char *kw_libc;
 const char *kw_main;
 const char *kw_memcmp;
 const char *kw_mainstub;
@@ -134,6 +135,7 @@ void symtab_init(uint32_t capacity)
 	type = TOKEN_IDENT;
 	kw_in = KW_DEF("in");
 	kw_inout = KW_DEF("inout");
+	kw_libc = KW_DEF("libc");
 	kw_mainstub = KW_DEF("_$main");
 	kw_main = KW_DEF("main");
 	kw_memcmp = KW_DEF("memcmp");

test/test_suite/functions/test_regression.c3t

@@ -555,51 +555,26 @@ entry:
 
 // #expect: foo.double.ll
 
-define double @"foo$double$.check"(double %0)
+define weak double @"foo$double$.check"(double %0)
 entry:
   %fmul = fmul double %0, %0
   ret double %fmul
 
-
-// #expect: test2.int.ll
-
-%Blob = type { i32 }
-@"test2$int$.argh" = local_unnamed_addr global i32 234, align 4
-
-define i32 @"test2$int$.getMult"(i32 %0) #0 {
-entry:
-  %mul = mul i32 %0, %0
-  ret i32 %mul
-}
-
-define i32 @"test2$int$.hello"() #0 {
-entry:
-  ret i32 1
-}
-
-define i32 @"test2$int$.getValue"(i32 %0) #0 {
-entry:
-  %blob = alloca %Blob, align 4
-  store i32 %0, ptr %blob, align 4
-  %1 = load i32, ptr %blob, align 4
-  ret i32 %1
-}
-
 // #expect: test2.double.ll
 
 %Blob = type { double }
-@"test2$double$.argh" = local_unnamed_addr global double 2.340000e+02, align 8
+@"test2$double$.argh" = weak local_unnamed_addr global double 2.340000e+02, align 8
 
-define double @"test2$double$.getMult"(double %0)
+define weak double @"test2$double$.getMult"(double %0)
 entry:
   %fmul = fmul double %0, %0
   ret double %fmul
 
-define i32 @"test2$double$.hello"()
+define weak i32 @"test2$double$.hello"()
 entry:
   ret i32 1
 
-define double @"test2$double$.getValue"(double %0)
+define weak double @"test2$double$.getValue"(double %0)
 entry:
   %blob = alloca %Blob, align 8
   store double %0, ptr %blob, align 8

test/test_suite/functions/test_regression_mingw.c3t

@@ -625,7 +625,7 @@ entry:
 
 // #expect: foo.double.ll
 
-define double @"foo$double$.check"(double %0)
+define weak double @"foo$double$.check"(double %0)
 entry:
   %fmul = fmul double %0, %0
   ret double %fmul
@@ -634,19 +634,18 @@ entry:
 // #expect: test2.int.ll
 
 %Blob = type { i32 }
-@"test2$int$.argh" = local_unnamed_addr global i32 234, align 4
+@"test2$int$.argh" = weak local_unnamed_addr global i32 234, comdat, align 4
 
-define i32 @"test2$int$.getMult"(i32 %0)
+define weak i32 @"test2$int$.getMult"(i32 %0)
 entry:
   %mul = mul i32 %0, %0
   ret i32 %mul
 
-define i32 @"test2$int$.hello"()
+define weak i32 @"test2$int$.hello"()
 entry:
   ret i32 1
 }
-
-define i32 @"test2$int$.getValue"(i32 %0)
+define weak i32 @"test2$int$.getValue"(i32 %0)
 entry:
   %blob = alloca %Blob, align 4
   store i32 %0, ptr %blob, align 4
@@ -657,22 +656,23 @@ entry:
 // #expect: test2.double.ll
 
 %Blob = type { double }
-@"test2$double$.argh" = local_unnamed_addr global double 2.340000e+02, align 8
 
-define double @"test2$double$.getMult"(double %0)
+
+@"test2$double$.argh" = weak local_unnamed_addr global double 2.340000e+02, comdat, align 8
+
+define weak double @"test2$double$.getMult"(double %0) #0 comdat {
 entry:
   %fmul = fmul double %0, %0
   ret double %fmul
 
-
-define i32 @"test2$double$.hello"()
+define weak i32 @"test2$double$.hello"() #0 comdat {
 entry:
   ret i32 1
+}
 
-define double @"test2$double$.getValue"(i64 %0)
+define weak double @"test2$double$.getValue"(i64 %0) #0 comdat {
 entry:
   %blob = alloca %Blob, align 8
   store i64 %0, ptr %blob, align 8
   %1 = load double, ptr %blob, align 8
   ret double %1
-

test/test_suite/generic/generic_idents.c3t

@@ -29,13 +29,13 @@ fn double getIt2(double i)
 
 /* #expect: gen.int.ll
 
-define i32 @"gen$int$.mult"(i32 %0) #0 {
+define weak i32 @"gen$int$.mult"(i32 %0) #0 {
 entry:
   %mul = mul i32 %0, %0
   ret i32 %mul
 }
 
-define i32 @"gen$int$.addMult"(i32 %0, i32 %1, i32 %2) #0 {
+define weak i32 @"gen$int$.addMult"(i32 %0, i32 %1, i32 %2) #0 {
 entry:
   %mul = mul i32 %0, %1
   %add = add i32 %mul, %2
@@ -58,14 +58,14 @@ entry:
   ret double %1
 }
 
-declare i32 @"gen$int$.mult"(i32)
+declare extern_weak i32 @"gen$int$.mult"(i32)
 
-declare double @"gen$double$.addMult"(double, double, double)
+declare extern_weak double @"gen$double$.addMult"(double, double, double)
 
 // #expect: gen.double.ll
 
 
-define double @"gen$double$.addMult"(double %0, double %1, double %2)
+define weak double @"gen$double$.addMult"(double %0, double %1, double %2)
 entry:
   %fmul = fmul double %0, %1
   %fadd = fadd double %fmul, %2

test/test_suite/generic/generic_over_fn.c3t

@@ -205,5 +205,5 @@ loop.exit:                                        ; preds = %loop.cond
   ret void
 }
 
+declare extern_weak void @"test_generic$sa$int$fn$int$int$$int$$.sort"(ptr, i64, i64, i64, ptr) #0
 
-declare void @"test_generic$sa$int$fn$int$int$$int$$.sort"(ptr, i64, i64, i64, ptr) #0

test/test_suite/import/access_other_module.c3t

@@ -9,7 +9,7 @@ fn void main()
 
 /* #expect: foo.ll
 
-@libc.EXIT_SUCCESS = external constant i32, align 4
+@libc.EXIT_SUCCESS = extern_weak constant i32, align 4
 
 define void @foo.main() #0 {
 entry: