diff --git a/compiler/src/dmd/cparse.d b/compiler/src/dmd/cparse.d
index a4e3c7ecc035..80b5c9aa79b1 100644
--- a/compiler/src/dmd/cparse.d
+++ b/compiler/src/dmd/cparse.d
@@ -5956,6 +5956,30 @@ final class CParser(AST) : Parser!AST
 
                     AST.Type t;
 
+                    bool hasMinus;
+                    if (token.value == TOK.min)
+                    {
+                        nextToken();
+                        // Only allow integer and float literals after minus.
+                        switch (token.value)
+                        {
+                            case TOK.int32Literal:
+                            case TOK.uns32Literal:
+                            case TOK.int64Literal:
+                            case TOK.uns64Literal:
+                            case TOK.float32Literal:
+                            case TOK.float64Literal:
+                            case TOK.float80Literal:
+                            case TOK.imaginary32Literal:
+                            case TOK.imaginary64Literal:
+                            case TOK.imaginary80Literal:
+                                hasMinus = true;
+                                break;
+                            default:
+                                continue;
+                        }
+                    }
+
                 Lswitch:
                     switch (token.value)
                     {
@@ -5980,6 +6004,8 @@ final class CParser(AST) : Parser!AST
                                  *  enum id = intvalue;
                                  */
                                 AST.Expression e = new AST.IntegerExp(scanloc, intvalue, t);
+                                if (hasMinus)
+                                    e = new AST.NegExp(scanloc, e);
                                 auto v = new AST.VarDeclaration(scanloc, t, id, new AST.ExpInitializer(scanloc, e), STC.manifest);
                                 addSym(v);
                                 ++p;
@@ -6003,6 +6029,8 @@ final class CParser(AST) : Parser!AST
                                  *  enum id = floatvalue;
                                  */
                                 AST.Expression e = new AST.RealExp(scanloc, floatvalue, t);
+                                if (hasMinus)
+                                    e = new AST.NegExp(scanloc, e);
                                 auto v = new AST.VarDeclaration(scanloc, t, id, new AST.ExpInitializer(scanloc, e), STC.manifest);
                                 addSym(v);
                                 ++p;
diff --git a/compiler/test/compilable/imports/defines.c b/compiler/test/compilable/imports/defines.c
index 6b0746f8ff96..420679a4fccb 100644
--- a/compiler/test/compilable/imports/defines.c
+++ b/compiler/test/compilable/imports/defines.c
@@ -55,3 +55,11 @@ int pr16199c()
 {
     return 8;
 }
+
+// https://issues.dlang.org/show_bug.cgi?id=24639
+#define NEGATIVE_I32 -1
+#define NEGATIVE_U32 -2U
+#define NEGATIVE_I64 -3LL
+#define NEGATIVE_U64 -4LLU
+#define NEGATIVE_F32 -5.0f
+#define NEGATIVE_F64 -6.0
diff --git a/compiler/test/compilable/testdefines.d b/compiler/test/compilable/testdefines.d
index 060e962920a6..58eefb7256a3 100644
--- a/compiler/test/compilable/testdefines.d
+++ b/compiler/test/compilable/testdefines.d
@@ -25,3 +25,17 @@ static assert(pr16199_ice == 3);
 
 static assert(pr16199d() == 7);
 static assert(pr16199c() == 8);
+
+// https://issues.dlang.org/show_bug.cgi?id=24639
+static assert(NEGATIVE_I32 == -1);
+static assert(NEGATIVE_U32 == cast(uint)-2);
+static assert(NEGATIVE_I64 == -3);
+static assert(NEGATIVE_U64 == cast(ulong)-4L);
+static assert(NEGATIVE_F32 == -5f);
+static assert(NEGATIVE_F64 == -6);
+static assert(is(typeof(NEGATIVE_I32) == int));
+static assert(is(typeof(NEGATIVE_U32) == uint));
+static assert(is(typeof(NEGATIVE_I64) == long));
+static assert(is(typeof(NEGATIVE_U64) == ulong));
+static assert(is(typeof(NEGATIVE_F32) == float));
+static assert(is(typeof(NEGATIVE_F64) == double));