I think your question might be based on a flawed assumption in the context of D&D's 5th edition. The rules for spellcasting include an informational block on The Weave which includes the line
All magic depends on the Weave...
A Warlock's pact magic is separated from other spellcasters in the rules because it comes from a pact made with a higher (ie powerful) being and not through innate talent, years of study, or a connection to a divine being that s/he worships.
However, the practical manifestation of magic is the same for all spellcasters (at least the mortal ones, at any rate) regardless of how they come by their ability: they must manipulate The Weave.
The Warlock class didn't exist until late in 3.5e. It was introduced in the supplemental sourcebook The Complete Arcane. Also introduced in that book was the Wild Mage prestige class.
Prestige classes were like specialized classes available to any character so long as they met the necessary entry requirements. A Warlock could eventually choose to take levels in the Wild Mage prestige class:
Magic is one of the most capricious and unpredictable of all natural or supernatural forces in the universe. Attempts to codify spellcasting through arcane formulas, or to impose order on magic through the force of will, are essentially pointless—or so wild mages believe. Instead, those who would truly master magic must forget what they know and abandon their willful control of the arcane. Within this paradox lies the awesome power of wild magic.
The wild mage aspires to cast spells without structure. By taking the risk of substituting an element of randomness, she gives up the safe predictability of other arcane spellcasters. This risk allows for the potential of power greater than other casters can hope for.
On page 69 of the Complete Arcane, one can find a call out block with the following:
Wild Mages in Faerûn
Wild mages are particularly adept at exploiting zones of wild magic, and they are much less likely to experience deleterious effects while casting spells within wild magic zones. Wild mages can roll twice on Table 2–1: Wild Magic Effects in Chapter 2 of the FORGOTTEN REALMS Campaign Setting and choose the preferred result.
In short, any caster, including a Warlock, could choose to explore and attempt to exploit wild magic.*
*User KRyan astutely points out that 3.5e Warlocks "do not wield spells" (per page 5 of The Complete Arcane) but get "Spell-like" Eldritch Invocations instead of actual spells. A strict reading of the rules technically allows them to take levels in the Wild Mage prestige class, which only require "Spells or Spell-Like Abilities." However, a couple of the Wild Mage features, namely Wild Magic and Reckless Dweomer, would be unusable by Warlocks as-written because, while the class allows characters who can use "spell-like abilities", those particular features specifically deal only with spells and spell slots, not "spell-like abilities."
That said, a DM can shape the lore of magic in 5th edition any way s/he desires. It would be perfectly reasonable to decide that divine magic and arcane magic function differently in your universe.